The latest news and insights from Google on security and safety on the Internet
An update on SHA-1 certificates in Chrome
December 18, 2015
Posted by Lucas Garron, Chrome security and David Benjamin, Chrome networking
announced last September
and supported by
further recent research
, Google Chrome does not treat SHA-1 certificates as secure anymore, and will completely stop supporting them over the next year. Chrome will discontinue support in two steps: first, blocking new SHA-1 certificates; and second, blocking all SHA-1 certificates.
Step 1: Blocking new SHA-1 certificates
Starting in early 2016 with Chrome version 48, Chrome will display a certificate error if it encounters a site with a leaf certificate that:
is signed with a SHA-1-based signature
is issued on or after January 1, 2016
chains to a public CA
We are hopeful that no one will encounter this error, since public CAs must stop issuing SHA-1 certificates in 2016 per the
Baseline Requirements for SSL
In addition, a later version of Chrome in 2016 may extend these criteria in order to help guard against SHA-1 collision attacks on older devices, by displaying a certificate error for sites with certificate chains that:
contain an intermediate or leaf certificate signed with a SHA-1-based signature
contain an intermediate or leaf certificate issued on or after January 1, 2016
chain to a public CA
(Note that the first two criteria can match different certificates.)
Note that sites using new SHA-1 certificates that chain to local trust anchors (rather than public CAs) will continue to work without a certificate error. However, they will still be subject to the UI downgrade specified in our
Step 2: Blocking all SHA-1 certificates
Starting January 1, 2017 at the latest, Chrome will completely stop supporting SHA-1 certificates. At this point, sites that have a SHA-1-based signature as part of the certificate chain (not including the self-signature on the root certificate) will trigger a fatal network error. This includes certificate chains that end in a local trust anchor as well as those that end at a public CA.
In line with
, the target date for this step is January 1, 2017, but we are considering moving it earlier to July 1, 2016 in light of ongoing research. We therefore urge sites to replace any remaining SHA-1 certificates as soon as possible.
Note that Chrome uses the certificate trust settings of the host OS where possible, and that an update such as Microsoft’s
will cause a fatal network error in Chrome, regardless of Chrome’s intended target date.
Keeping your site safe and compatible
As individual TLS features are found to be too weak, browsers need to drop support for those features to keep users safe. Unfortunately, SHA-1 certificates are not the only feature that browsers will remove in the near future.
on our security-dev mailing list, Chrome 48 will also stop supporting RC4 cipher suites for TLS connections. This aligns with timelines for
For security and interoperability in the face of upcoming browser changes, site operators should ensure that their servers use SHA-2 certificates, support non-RC4 cipher suites, and follow TLS best practices. In particular, we recommend that most sites support TLS 1.2 and prioritize the ECDHE_RSA_WITH_AES_128_GCM cipher suite. We also encourage site operators to use tools like the
SSL Labs server test
Mozilla's SSL Configuration Generator
Indexing HTTPS pages by default
December 17, 2015
Zineb Ait Bahajji
, WTA, and the Google Security and Indexing teams
[Cross-posted from the
Webmaster Central Blog
At Google, user security has always been a top priority. Over the years, we’ve worked hard to promote a more secure web and to provide a better browsing experience for users.
, and YouTube have had secure connections for some time, and we also started giving a slight
ranking boost to HTTPS URLs
in search results last year. Browsing the web should be a private experience between the user and the website, and must not be subject to
, or data modification. This is why we’ve been strongly promoting
As a natural continuation of this, today we'd like to announce that we're adjusting our indexing system to look for more HTTPS pages. Specifically, we’ll start crawling HTTPS equivalents of HTTP pages, even when the former are not linked to from any page. When two URLs from the same domain appear to have the same content but are served over different protocol schemes, we’ll typically choose to index the HTTPS URL if:
It doesn’t contain insecure dependencies.
It isn’t blocked from crawling by robots.txt.
It doesn’t redirect users to or through an insecure HTTP page.
It doesn’t have a rel="canonical" link to the HTTP page.
It doesn’t contain a noindex robots meta tag.
It doesn’t have on-host outlinks to HTTP URLs.
The sitemaps lists the HTTPS URL, or doesn’t list the HTTP version of the URL.
The server has a valid TLS certificate.
Although our systems prefer the HTTPS version by default, you can also make this clearer for other search engines by redirecting your HTTP site to your HTTPS version and by implementing the
on your server.
We’re excited about taking another step forward in making the web more secure. By showing users HTTPS pages in our search results, we’re hoping to decrease the risk for users to browse a website over an insecure connection and making themselves vulnerable to content injection attacks. As usual, if you have any questions or comments, please let us know in the comments section below or in our
webmaster help forums
Proactive measures in digital certificate security
December 11, 2015
Posted by Ryan Sleevi, Software Engineer
Over the course of the coming weeks, Google will be moving to distrust the “Class 3 Public Primary CA” root certificate operated by Symantec Corporation, across Chrome, Android, and Google products. We are taking this action in response to a
notification by Symantec Corporation
that, as of December 1, 2015, Symantec has decided that this root will no longer comply with the
CA/Browser Forum’s Baseline Requirements
. As these requirements reflect industry best practice and are the foundation for publicly trusted certificates, the failure to comply with these represents an unacceptable risk to users of Google products.
Symantec has informed us they intend to use this root certificate for purposes other than publicly-trusted certificates. However, as this root certificate will no longer adhere to the CA/Browser Forum’s Baseline Requirements, Google is no longer able to ensure that the root certificate, or certificates issued from this root certificate, will not be used to intercept, disrupt, or impersonate the secure communication of Google’s products or users. As Symantec is unwilling to specify the new purposes for these certificates, and as they are aware of the risk to Google’s users, they have requested that Google take preventative action by removing and distrusting this root certificate. This step is necessary because this root certificate is widely trusted on platforms such as Android, Windows, and versions of OS X prior to OS X 10.11, and thus certificates Symantec issues under this root certificate would otherwise be treated as trustworthy.
Symantec has indicated that they do not believe their customers, who are the operators of secure websites, will be affected by this removal. Further, Symantec has also indicated that, to the best of their knowledge, they do not believe customers who attempt to access sites secured with Symantec certificates will be affected by this. Users or site operators who encounter issues with this distrusting and removal should
contact Symantec Technical Support
Further Technical Details of Affected Root:
Class 3 Public Primary Certification Authority
C=US, O=VeriSign, Inc., OU=Class 3 Public Primary Certification Authority
Public Key Hash (SHA-1):
Public Key Hash (SHA-256):
Year one: progress in the fight against Unwanted Software
December 9, 2015
Posted by Moheeb Abu Rajab, Google Security Team
“At least 2 or 3 times a week I get a big blue warning screen with a loud voice telling me that I’ve a virus and to call the number at the end of the big blue warning.”
“I’m covered with ads and unwanted interruptions. what’s the fix?”
“I WORK FROM HOME AND THIS POPING [sic] UP AND RUNNING ALL OVER MY COMPUTER IS NOT RESPECTFUL AT ALL THANK YOU.”
Launched in 2007
, Safe Browsing has long helped protect people across the web from well-known online dangers like phishing and malware. More recently, however, we’ve seen an increase in user complaints like the ones above. These issues and others—hijacked browser settings, software installed without users' permission that resists attempts to uninstall—have signaled the rise of a new type of malware that our systems haven’t been able to reliably detect.
More than a year ago
, we began a broad fight against this category of badness that we now call “Unwanted Software”, or “UwS” (pronounced “ooze”). Today, we wanted to share some progress and outline the work that must happen in order to continue protecting users across the web.
What is UwS and how does it get on my computer?
In order to combat UwS, we first needed to define it. Despite lots of variety, our research enabled us to develop a
defining list of characteristics
that this type of software often displays:
It is deceptive, promising a value proposition that it does not meet.
It tries to trick users into installing it or it piggybacks on the installation of another program.
It doesn’t tell the user about all of its principal and significant functions.
It affects the user’s system in unexpected ways.
It is difficult to remove.
It collects or transmits private information without the user’s knowledge.
It is bundled with other software and its presence is not disclosed.
Next, we had to better understand how UwS is being disseminated.
This varies quite a bit, but time and again, deception is at the heart of these tactics. Common UwS distribution tactics include:
unwanted ad injection
, misleading ads such as “trick-to-click”, ads disguised as ‘download’ or ‘play’ buttons, bad software downloader practices, misleading or missing disclosures about what the software does, hijacked browser default settings, annoying system pop-up messages, and more.
Here are a few specific examples:
Deceptive ads leading to UwS downloads
Ads from unwanted ads injector taking over a New York Times page and sending the user to phone scams
Unwanted ad injector inserts ads on the Google search results page
New tab page is overridden by UwS
UwS hijacks Chrome navigations and directs users to a scam tech support website
One year of progress
Because UwS touches so many different parts of people’s online experiences, we’ve worked to fight it on many different fronts. Weaving UwS detection into Safe Browsing has been critical to this work, and we’ve pursued other efforts as well—here’s an overview:
We now include UwS in
, enabling people who use Chrome and other browsers to see warnings before they go to sites that contain UwS. The red warning below appears in Chrome.
We launched the
Chrome Cleanup Tool
, a one-shot UwS removal tool that has helped clean more than 40 million devices. We shed more light on a common symptom of UwS—
unwanted ad injectors
. We outlined
how they make money
launched a new filter
in DoubleClick Bid Manager that removes impressions generated by unwanted ad injectors before bids are made.
We started using
UwS as a signal in search
to reduce the likelihood that sites with UwS would appear in search results.
Google ads that lead to sites with UwS downloads.
It’s still early, but these changes have already begun to move the needle.
UwS-related Chrome user complaints have fallen. Last year, before we rolled-out our new policies, these were 40% of total complaints and now they’re 20%.
We’re now showing more than 5 million Safe Browsing warnings per day on Chrome related to UwS to ensure users are aware of a site’s potential risks.
We helped more than 14 million users remove over 190 deceptive Chrome extensions from their devices.
reduced the number of UwS warnings
that users see via AdWords by 95%, compared to last year. Even prior to last year, less than 1% of UwS downloads were due to AdWords.
However, there is still a long way to go. 20% of all feedback from Chrome users is related to UwS and we believe 1 in 10 Chrome users have hijacked settings or unwanted ad injectors on their machines. We expect users of other browsers continue to suffer from similar issues; there is lots of work still to be done.
Looking ahead: broad industry participation is essential
Given the complexity of the UwS ecosystem, the involvement of players across the industry is key to making meaningful progress in this fight. This chain is only as strong as its weakest links: everyone must work to develop and enforce strict, clear policies related to major sources of UwS.
If we’re able, as an industry, to enforce these policies, then everyone will be able to provide better experiences for their users. With this in mind, we’re very pleased to see that the
FTC recently warned consumers
about UwS and characterizes UwS as a
form of malware
. This is an important step toward uniting the online community and focusing good actors on the common goal of eliminating UwS.
We’re still in the earliest stages of the fight against UwS, but we’re moving in the right direction. We’ll continue our efforts to protect users from UwS and work across the industry to eliminate these bad practices.
A new version of Authenticator for Android
December 7, 2015
Posted by Alexei Czeskis, Software Engineer
Authenticator for Android is used by millions of users and, combined with
, it provides an extra layer of protection for Google Accounts.
Our latest version has some cool new features. You will notice a new icon and a refreshed design. There's also support for
devices, so you'll be able to get verification codes from compatible devices, like your watch.
The new Authenticator also comes with a developer preview of support for NFC Security Key, based on the FIDO Universal 2nd Factor (U2F) protocol via NFC. Play Store will prompt for the NFC permission before you install this version of Authenticator.
Developers who want to learn more about U2F can refer to FIDO's
. Additionally, you can try it out at
. Note that you'll need an Android device running the latest versions of Google Chrome and Authenticator and also a
with NFC support.
You can find the latest
Authenticator for Android on the Play Store
Protecting hundreds of millions more mobile users
December 7, 2015
Posted by Noé Lutz, Nathan Parker, Stephan Somogyi; Google Chrome and Safe Browsing Teams
Google Safe Browsing has been protecting well over a billion desktop users against
malware, unwanted software, and social engineering sites
on the web for years. Today, we’re pleased to announce that we’ve extended our protective umbrella to hundreds of millions of Chrome users on Android.
How To Get It
If you’re an Android user, you probably already have it! This new Safe Browsing client on Android is part of Google Play Services, starting with version 8.1. The first app to use it is Chrome, starting with version 46—we’re now protecting all Android Chrome users by default. If you look at Chrome’s Settings > Privacy menu, you can verify that Safe Browsing is enabled and that you’re protected. Chrome warns you about dangerous sites as shown below. It does this
while preserving your privacy, just like on desktop
What Came Before
The Android platform and the Play Store have long had protection against potentially harmful apps. And as our adversaries have improved their skills in trying to evade us, we’ve improved our detection, keeping Android app users safe. But not all dangers to mobile users come from apps.
—and phishing in particular—requires different protection; we need to keep an up-to-date list of bad sites on the device to make sure we can warn people before they browse into a trap. Providing this protection on a mobile device is much more difficult than on a desktop system, in no small part because we have to make sure that list doesn’t get stale, yet:
Mobile data costs money for most users around the world. Data size matters a lot.
Mobile data speeds are slower than Wi-Fi in much of the world. Data size matters a lot.
Cellular connectivity quality is much more uneven, so getting the right data to the device quickly is critically important. Data size matters a lot.
Maximum Protection Per Bit
Bytes are big: our mantra is that every single bit that Safe Browsing sends a mobile device must improve protection. Network bandwidth and battery are the scarcest resources on a mobile device, so we had to carefully rethink how to best protect mobile users. Some social engineering attacks only happen in certain parts of the world, so we only send information that protects devices in the geographic regions they’re in.
We also make sure that we send information about the riskiest sites first: if we can only get a very short update through, as is often the case on lower-speed networks in emerging economies, the update really has to count. We also worked with Google’s compression team to make the little data that we do send as small as possible.
Together with the Android Security team, we made the software on the device extra stingy with memory and processor use, and careful about minimizing network traffic. All of these details matter to us; we must not waste our users’ data plans, or a single moment of their battery life.
We hunt badness on the Internet so that you don’t discover it the hard way, and our protection should never be an undue burden on your networking costs or your device’s battery. As more of the world relies on the mobile web, we want to make sure you’re as safe as can be, as efficiently as possible.
Safe Browsing protection from even more deceptive attacks
November 13, 2015
Posted by Emily Schechter, Program Manager and Noé Lutz, Software Engineer
has been protecting over one billion people from
traditional phishing attacks
on the web for more than eight years. The threat landscape is constantly changing—bad actors on the web are using more and different types of deceptive behavior to trick you into performing actions that you didn’t intend or want, so we’ve expanded protection to include social engineering.
Social engineering is a much broader category than traditional phishing and encompasses more types of deceptive web content. A social engineering attack happens when either:
The content pretends to act, or looks and feels, like a trusted entity — like a bank or government.
The content tries to trick you into doing something you’d only do for a trusted entity — like sharing a password or calling tech support.
Below are some examples of social engineering attacks that try to trick you into thinking the content is delivered by Google or Chrome. Other trusted brands are also commonly abused for social engineering attacks.
This page tries to trick you into downloading and executing malware or unwanted software. It uses Chrome’s logo and name to confuse you into believing the site is operated by Google. Content like this may include an inconspicuous legal disclaimer that states it is not affiliated with Google. This does not change the deceptive nature of this content—as always, use caution when downloading files from the web.
This is a fake tech phone support page. This page mimics a warning and may trick you into calling a third-party company that pretends to be Google or some other trusted entity, but charges a fee for support. (Chrome does not offer paid remote support).
This is a fake Google login page. It might trick you into disclosing your account login credentials. Other phishing sites like this could trick you into giving up other personal information such as credit card information. Phishing sites may look exactly like the real site—so be sure to look at the address bar to check that the URL is correct, and also check to see that the website begins with https://. See more information
If we identify that a web page contains social engineering content, Chrome will warn you by displaying the following warning:
(If you believe Safe Browsing has classified a web page in error, please report it
We'll continue to improve Google's Safe Browsing protection to help more people stay safer online. Check out the
Safe Browsing Transparency Report
to find out more.
New Research: Encouraging trends and emerging threats in email security
November 12, 2015
Posted by Elie Bursztein, Anti-Fraud and Abuse Research and Nicolas Lidzborski, Gmail Security Engineering Lead
We’re constantly working to help make email more secure for everyone. These efforts are reflected in security protections like
in Gmail as well as our
Safer Email Transparency report
, which includes information about email security beyond just Gmail.
To that end, in partnership with the University of Michigan and the University of Illinois, we’re publishing the results of a
that measured how email security has evolved since 2013. While Gmail was the foundation of this research, the study’s insights apply to email more broadly, not unlike our
Safer Email Transparency report
. It’s our hope that these findings not only help make Gmail more secure, but will also be used to help protect email users everywhere as well.
Email security strengthens, industry-wide
The study showed that email is more secure today than it was two years ago. Here are some specific findings:
Newer security challenges and how we can address them
Our study identified several new security challenges as well.
First, we found regions of the Internet actively preventing message encryption by tampering with requests to initiate SSL connections. To mitigate this attack, we are working closely with partners through the industry association
to strengthen “opportunistic TLS” using technologies that we pioneered with Chrome to protect websites against interception.
Second, we uncovered malicious DNS servers publishing bogus routing information to email servers looking for Gmail. These nefarious servers are like telephone directories that intentionally list misleading phone numbers for a given name. While this type of attack is rare, it’s very concerning as it could allow attackers to censor or alter messages before they are relayed to the email recipient.
While these threats do not affect Gmail to Gmail communication, they may affect messaging between providers. To notify our users of potential dangers, we are developing in-product warnings for Gmail users that will display when they receive a message through a non-encrypted connection. These warnings will begin to roll-out in the coming months.
All email services—Gmail included—depend on the trust of their users. Partnering with top researchers helps us make the email ecosystem as a whole safer and more secure for everyone. Security threats won’t disappear, but studies like these enable providers across the industry to fight them with better, more powerful protections today and going forward.
[This work was made possible thanks to the contribution of many Googlers including Vijay Eranti, Kurt Thomas, John Rae-Grant, and Mark Risher.]
Sustaining Digital Certificate Security
October 28, 2015
Posted by Ryan Sleevi, Software Engineer
This post updates our
of a misissued certificate for google.com
Following our notification, Symantec published
in response to our inquiries and disclosed that 23 test certificates had been issued without the domain owner’s knowledge covering five organizations, including Google and Opera.
However, we were still able to find several more questionable certificates using only the Certificate Transparency logs and a few minutes of work. We shared these results with other root store operators on October 6th, to allow them to independently assess and verify our research.
Symantec performed another audit and, on October 12th, announced that they had found an additional
over 76 domains and
issued for domains that were never registered.
It’s obviously concerning that a CA would have such a long-running issue and that they would be unable to assess its scope after being alerted to it and conducting an audit. Therefore we are firstly going to require that as of June 1st, 2016, all certificates issued by Symantec itself will be required to support Certificate Transparency. In this case, logging of non-EV certificates would have provided significantly greater insight into the problem and may have allowed the problem to be detected sooner.
After this date, certificates newly issued by Symantec that do not conform to the Chromium Certificate Transparency policy may result in interstitials or other problems when used in Google products.
More immediately, we are requesting of Symantec that they further update their public incident report with:
A post-mortem analysis that details why they did not detect the additional certificates that we found.
Details of each of the failures to uphold the relevant Baseline Requirements and EV Guidelines and what they believe the individual root cause was for each failure.
We are also requesting that Symantec provide us with a detailed set of steps they will take to correct and prevent each of the identified failures, as well as a timeline for when they expect to complete such work. Symantec may consider this latter information to be confidential and so we are not requesting that this be made public.
Following the implementation of these corrective steps, we expect Symantec to undergo a Point-in-time Readiness Assessment and a third-party security audit. The point-in-time assessment will establish Symantec’s conformance to each of these standards:
WebTrust Principles and Criteria for Certification Authorities
WebTrust Principles and Criteria for Certification Authorities – SSL Baseline with Network Security
WebTrust Principles and Criteria for Certification Authorities – Extended Validation SSL
The third-party security audit must assess:
The veracity of Symantec’s claims that at no time private keys were exposed to Symantec employees by the tool.
That Symantec employees could not use the tool in question to obtain certificates for which the employee controlled the private key.
That Symantec’s audit logging mechanism is reasonably protected from modification, deletion, or tampering, as described in Section 5.4.4 of their CPS.
We may take further action as additional information becomes available to us.
Behind the red warning: more info about online site safety
October 20, 2015
Adrienne Porter Felt, Chrome Security Engineer and Warning Wizard
Emily Schechter, Safe Browsing Program Manager and Menace to Malware
Ke Wang, Safe Browsing Engineer and Developer of Defense
You’re browsing the web, checking out the latest news on your favorite band, when suddenly you see a red warning screen: “The site ahead contains malware.” These warnings aren’t new—since 2006, Google Safe Browsing has shown them when you navigate to an unsafe site. The warnings protect you from harms caused by unsafe sites, such as malware infections and phishing attacks. But it hasn’t always been clear why a specific website triggers a warning, and you may want to learn more.
To demystify these warnings, we’re launching a
Site Status section
in the Transparency Report. The next time you come across a Safe Browsing warning, you can search for the blocked website in the Transparency Report to learn why it’s been flagged by our systems.
The new Site Status section of the Transparency Report replaces our previous
Safe Browsing diagnostic page
. It includes a clearer interface and simpler explanations of the issues, such as details for sites that host
. We’ve added it to the Transparency Report so that the Safe Browsing section of the report is a one-stop shop for information to help you understand what Safe Browsing is and how it works.
If a favorite website shows up as “dangerous,” it’s often due to user-uploaded bad content or a temporary malware infection. The Site Status will return to normal once the webmaster has cleaned up the website. To help speed up this process, we automatically give the webmaster a heads-up about the problem via
; if you use
, we’ll also warn you there if your site has malware on it. (Webmasters, check the
to learn how to remove malware from your websites.)
We’re constantly working to keep users safe and informed online. Visit the updated Site Status section in the
to experience it yourself.
Simplifying the Page Security Icon in Chrome
October 13, 2015
Posted by Lucas Garron and Chris Palmer, Chrome security team
Sometimes, websites try to use HTTPS to be secure and get it mostly right, but they have minor errors. Until recently, Chrome marked this security state with a yellow “caution triangle” badge on the page security icon in the URL bar.
Starting with version 46, Chrome will mark the “HTTPS with Minor Errors” state using the same neutral page icon as HTTP pages.
There are two reasons for this:
This change is a better visual indication of the security state of the page relative to HTTP.
Chrome users will have fewer security states to learn.
(Not) Warning About Mixed Content
This change will mainly affect HTTPS pages that contain certain
, such as HTTP images.
Site operators face a dilemma: Switching an HTTP site to HTTPS can initially result in mixed content, which is undesirable in the long term but important for debugging the migration. During this process the site may not be fully secured, but it will usually not be less secure than before.
Removing the yellow “caution triangle” badge means that most users will not perceive a warning on mixed content pages during such a migration. We hope that this will encourage site operators to switch to HTTPS sooner rather than later.
Fewer Security States
This change will reduce the number of page security states in Chrome from four to three.
We have to strike a balance: representing the security state of a webpage as accurately as possible, while making sure users are not overwhelmed with too many possible states and details. We’ve come to understand that our yellow “caution triangle” badge can be confusing when compared to the HTTP page icon, and we believe that it is better not to emphasize the difference in security between these two states to most users. For developers and other interested users, it will still be possible to tell the difference by checking whether the URL begins with “https://”.
In the long term, we hope that most sites on the internet will become secure, and we
to reduce the icon to just two states: secure and not secure. The change announced in this post is a small step in that direction.
HTTPS support coming to Blogspot
September 30, 2015
Posted by Jo-el van Bergen, Software Engineer, Security.
, we've worked to encrypt the connections between our users and Google servers. Over the years we've announced that Search, Gmail, Drive, and many other products have encrypted connections by default, and most recently, we've made a similar announcement for
our ads products
In this same vein, today we're expanding on the
mission and beginning an initial rollout of HTTPS support for Blogspot. HTTPS is a cornerstone of internet security as it provides several important benefits: it makes it harder for bad actors to steal information or track the activities of blog authors and visitors, it helps check that visitors open the correct website and aren’t being redirected to a malicious location, and it helps detect if a bad actor tries to change any data sent from Blogger to a blog visitor.
While this initial rollout won’t support all of our Blogger users, we wanted to take the first step to make HTTPS available for Blogspot; for those users who want to try it early.
We’re rolling this out gradually and Blogspot authors interested in enabling HTTPS support can begin opting-in today. Simply log into
, click on the blog you’d like to make HTTPS enabled, navigate to the Settings page, and select "yes" for "HTTPS Availability". Unfortunately, blogs with custom domains are not supported in this first version.
Once enabled, your blog will become accessible over both HTTP and HTTPS connections. Blogspot authors should be aware that if they choose to encrypt at this time, some of the current functionality of their blog may not work over HTTPS. This can be a result of template, gadgets, and blog post content, and is often caused by
errors, some of which may be
fixable by the author themselves
We’ll also be moving some of our own blogs over to HTTPS gradually, beginning with the
Official Google Blog
Google Online Security Blog
For the Blogspot authors who try this out - we’re interested to hear your
while we continue to improve this feature and its capabilities! For more information, visit our
New research: The underground market fueling for-profit abuse
September 24, 2015
Posted by Kurt Thomas and Elie Bursztein, Google Anti-Fraud and Abuse Research
Recently, we teamed up with top researchers exploring innovative anti-abuse strategies to build a holistic understanding of for-profit abuse. The full report, which you can read
, was presented in June at the
Workshop on the Economics of Information Security
Over the last decade, Internet crime has matured into an underground economy where a large number of globally distributed criminals trade in data, knowledge, and services specifically geared towards defrauding users and businesses. Within this black market, criminals buy and sell compromised machines, scam hosting, exploit kits, and wholesale access to pilfered user records including usernames and passwords, credit card numbers, and other sensitive personal data. The availability of such specialized resources has transformed for-profit abuse into a cooperative effort among criminals each satisfying a cog in a supply chain.
Profiting from abuse: a bird's eye view
Here’s an example of the underground value chain required to make money from spamming knock-off luxury products:
In aggregate, the problem may appear intractable to stop. However, if we view this scenario in an economic light, then increasing the cost of fake accounts, phone numbers, or compromised websites cuts into the profitability of abuse. In the end, abuse propped up by cost-ineffective resources will crumble.
Collaborating to better understand the underground
Given the complex underbelly of abuse, we pulled together experts from industry and academia to build a systematic understanding of how criminals operate. Our previous example represents just one configuration of a value chain. In our example, revenue originates solely from victims buying counterfeit products. Criminals could adapt this strategy to scam users into paying for fake anti-virus, defraud advertisers via clickbots, or liquidate a victim’s banking assets. Regardless of the composition, we argue there is always a profit center through which victims transfer new capital into the underground. These schemes form a spectrum between selling products to unwitting victims to outright theft. A medley of alternatives such as dating scams, call-center scams, premium SMS fraud, DDoS extortion, or even stealing and re-selling gaming assets all fall within this spectrum and ultimately derive a payout from victims outside the underground.
These profit centers are in turn propped up by an ecosystem of support infrastructure that can be configured arbitrarily by criminals per their requirements. This infrastructure includes compromised hosts, human labor, networking and hosting, and accounts and engagement—all available for a fee. For example, 1,000 Google accounts cost on the order of $170, compared to CAPTCHAs which cost $1 per thousand. These costs reflect socio-economic factors as well as the impact of technical, legal, and law enforcement interventions on the availability of resources.
Redefining the abuse arms race
Client and server-side security has dominated industry’s response to digital abuse over the last decade. The spectrum of solutions—automated software updates, personal anti-virus, network packet scanners, firewalls, spam filters, password managers, and two-factor authentication to name a few—all attempt to reduce the attack surface that criminals can penetrate.
While these safeguards have significantly improved user security, they create an arms race: criminals adapt or find the subset of systems that remain vulnerable and resume operation. To overcome this reactive defense cycle, we are improving our approach to abuse fighting to also strike at the support infrastructure, financial centers, and actors that incentivize abuse. By exploring the value chain required to bulk register accounts, we were able to make Google accounts
30–40% more expensive on the black market
Success stories from our academic partners include
disrupting payment processing
for illegal pharmacies and counterfeit software outlets advertised by spam,
cutting off access to fake accounts
that pollute online services, and
disabling the command and control
infrastructure of botnets.
Improved Digital Certificate Security
September 18, 2015
Posted by Stephan Somogyi, Security & Privacy PM, and Adam Eijdenberg, Certificate Transparency PM
On September 14, around 19:20 GMT, Symantec’s Thawte-branded CA issued an Extended Validation (EV) pre-certificate for the domains
. This pre-certificate was neither requested nor authorized by Google.
We discovered this issuance via
logs, which Chrome has required for EV certificates starting January 1st of this year. The issuance of this pre-certificate was recorded in both Google-operated and DigiCert-operated logs.
During our ongoing discussions with Symantec we determined that the issuance occurred during a Symantec-internal testing process.
We have updated Chrome’s revocation metadata to include the public key of the misissued certificate. Additionally, the issued pre-certificate was valid only for one day.
Our primary consideration in these situations is always the security and privacy of our users; we currently do not have reason to believe they were at risk.
Disabling SSLv3 and RC4
September 17, 2015
Posted by Adam Langley, Security Engineer
transition to SHA-256 certificates is nearing completion, we are planning the next changes to Google’s TLS configuration. As part of those changes, we expect to disable support for SSLv3 and RC4 in the medium term.
SSLv3 has been
for over 16 years and is so full of known problems that the IETF has decided that it
must no longer be used
. RC4 is a 28 year old cipher that has done remarkably well, but is now the subject of
at security conferences. The IETF has decided that RC4 also warrants a statement that it too
must no longer be used
Because of these issues we expect to disable both SSLv3 and RC4 support at Google’s frontend servers and, over time, across our products in general, including Chrome, Android, our webcrawlers and our SMTP servers. (Indeed, SSLv3 support has already been removed from Chrome.) The
survey of the top 200,000 HTTPS sites finds that, already, 42% of sites have disabled RC4 and 65% of sites have disabled SSLv3.
If your TLS client, webserver or email server requires the use of SSLv3 or RC4 then the time to update was some years ago, but better late than never. However, note that just because you might be using RC4 today doesn’t mean that your client or website will stop working: TLS can negotiate cipher suites and problems will only occur if you don’t support anything but RC4. (Although if you’re using SSLv3 today then things will stop working when we disable it because SSLv3 is already a last resort.)
Minimum standards for TLS clients
Google's frontend servers do a lot more than terminate connections for browsers these days; there are also lots of embedded systems talking to Google using TLS. In order to reduce the amount of work that the deprecation of outdated cryptography causes, we are also announcing suggested minimum standards for TLS clients today. This applies to TLS clients in general: certainly those that are using TLS as part of HTTPS, but also, for example, SMTP servers using STARTTLS.
We can't predict the future, but devices that meet these requirements are likely to be able to continue functioning without changes to their TLS configuration up to 2020. You should expect these standards to be required in cases where Google runs certification programs, but it’s a very good idea to meet them anyway.
Devices that don’t meet these standards aren’t going to stop working anytime soon (unless they depend on RC4 or SSLv3—see above), but they might be affected by further TLS changes in the coming years.
Specifically, we are requiring:
TLS 1.2 must be supported.
A Server Name Indication (SNI) extension must be included in the handshake and must contain the domain that's being connected to.
The cipher suite TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 must be supported with P-256 and uncompressed points.
At least the certificates in
must be trusted.
Certificate handling must be able to support DNS Subject Alternative Names and those SANs may include a single wildcard as the left-most label in the name.
In order to make testing as easy as possible we have set up
, which requires points 1–3 to be met in order to make a successful connection. Thus, if your TLS client can’t connect to that host then you need to update your libraries or configuration.
No longer serving a cross-sign to Equifax
At the moment the certificate chains that Google properties serve most often include a cross-sign from our CA, GeoTrust, to our previous CA, Equifax. This allows clients that only trust our previous CA to continue to function. However, this cross-sign is only a transitional workaround for such clients and we will be removing it in the future. Clients that include our required set of root CAs (at
) will not be affected, but any that don’t include the needed GeoTrust root may stop working.
Cutting unwanted ad injectors out of advertising
September 10, 2015
Posted by Vegard Johnsen, Product Manager, Google Ads Traffic Quality
For the last few months, we’ve been raising awareness of the ad injection economy, showing how unwanted ad injectors can
hurt user experience
jeopardize user security
generate significant volumes of unwanted ads
. We’ve used learnings from
to prevent and remove unwanted ad injectors from Google services and improve our policies and technologies to make it more difficult to spread this unwanted software.
Today, we’re announcing a new measure to remove injected ads from the advertising ecosystem, including an automated filter in DoubleClick Bid Manager that removes impressions generated by ad injectors before any bid is made.
Unwanted ad injectors: disliked by users, advertisers, and publishers
Unwanted ad injectors are programs that insert new ads, or replace existing ones, in the pages users visit while browsing the web. Unwanted ad injectors aren’t part of a healthy ads ecosystem. They’re part of an environment where bad practices hurt users, advertisers, and publishers alike.
We’ve received almost 300,000 user complaints about them in Chrome since the beginning of 2015—more than any other issue, and it’s no wonder. Ad injectors affect all sites equally. You wouldn’t be happy if you tried to get the morning news and saw this:
Not only are they intrusive, but people are often tricked into installing them in the first place, via deceptive advertising, or software “bundles.” Ad injection can also be a security risk, as the
recent “Superfish” incident
Ad injectors are problematic for advertisers and publishers as well. Advertisers often don’t know their ads are being injected, which means they don’t have any idea where their ads are running. Publishers, meanwhile, aren’t being compensated for these ads, and more importantly, they unknowingly may be putting their visitors in harm’s way, via spam or malware in the injected ads.
Removing injected inventory from advertising
Earlier this quarter, we launched an automated filter on DoubleClick Bid Manager to prevent advertisers from buying injected ads across the web. This new system detects ad injection and proactively creates a blacklist that prevents our systems from bidding on injected inventory. Advertisers and agencies using our platforms are already protected. No adjustments are needed. No settings to change.
We currently blacklist 1.4% of the inventory accessed by DoubleClick Bid Manager across exchanges. However, we’ve found this percentage varies widely by provider. Below is a breakdown showing the filtered percentages across some of the largest exchanges:
We’ve always enforced
the sale of injected inventory on our ads platforms, including the DoubleClick Ad Exchange. Now advertisers using DoubleClick Bid Manager can avoid injected inventory across the web.
No more injected ads?
We don’t expect the steps we’ve outlined above to solve the problem overnight, but we hope others across the industry take action to cut ad injectors out of advertising. With the tangle of different businesses involved—knowingly, or unknowingly—in the ad injector ecosystem, progress will only be made if we all work together. We strongly encourage all members of the ads ecosystem to review their policies and practices and take actions to tackle this issue.
Say hello to the Enigma conference
August 18, 2015
Posted by Elie Bursztein - Anti-abuse team, Parisa Tabriz - Chrome Security and Niels Provos - Security team
is a new conference focused on security, privacy and electronic crime through the lens of emerging threats and novel attacks. The goal of this conference is to help industry, academic, and public-sector practitioners better understand the threat landscape. Enigma will have a single track of 30-minute talks that are curated by a panel of experts, featuring strong technical content with practical applications to current and emerging threats.
Google is excited to both sponsor and help USENIX build Enigma, since we share many of its core principles: transparency, openness, and cutting-edge security research. Furthermore, we are proud to provide Enigma with with engineering and design support, as well as volunteer participation in program and steering committees.
The first instantiation of Enigma will be held January 25-27 in San Francisco. You can sign up for more information about the conference or propose a talk through the official conference site at
New research: Comparing how security experts and non-experts stay safe online
July 23, 2015
Iulia Ion, Software Engineer - Rob Reeder, Research Scientist - Sunny Consolvo, User Experience Researcher
Today, you can find more online security tips in a few seconds than you could use in a lifetime. While this collection of best practices is rich, it’s not always useful; it can be difficult to know which ones to prioritize, and why.
Questions like ‘Why do people make some security choices (and not others)?’ and ‘How effectively does the security community communicate its best practices?’ are at the heart of a new paper called, “...no one can hack my mind”: Comparing Expert and Non-Expert Security Practices” that we’ll present this week at the
Symposium on Usable Privacy and Security
This paper outlines the results of two surveys—one with 231 security experts, and another with 294 web-users who aren’t security experts—in which we asked both groups what they do to stay safe online. We wanted to compare and contrast responses from the two groups, and better understand differences and why they may exist.
Experts’ and non-experts’ top 5 security practices
Here are experts’ and non-experts’ top security practices, according to our study. We asked each participant to list 3 practices:
Common ground: careful password management
Clearly, careful password management is a priority for both groups. But, they differ on their approaches.
Security experts rely heavily on password managers, services that store and protect all of a user’s passwords in one place. Experts reported using password managers, for at least some of their accounts, three-times more frequently than non-experts.
As one expert said, “Password managers change the whole calculus because they make it possible to have both strong and unique passwords.”
On the other hand, only 24% of non-experts reported using password managers for at least some of their accounts, compared to 73% of experts. Our findings suggested this was due to lack of education about the benefits of password managers and/or a perceived lack of trust in these programs. “I try to remember my passwords because no one can hack my mind,” one non-expert told us.
Key differences: software updates and antivirus software
Despite some overlap, experts’ and non-experts’ top answers were remarkably different.
35% of experts and only 2% of non-experts said that installing software updates was one of their top security practices. Experts recognize the benefits of updates—“Patch, patch, patch,” said one expert—while non-experts not only aren’t clear on them, but are concerned about the potential risks of software updates. A non-expert told us: “I don’t know if updating software is always safe. What [if] you download malicious software?” and “Automatic software updates are not safe in my opinion, since it can be abused to update malicious content.”
Meanwhile, 42% of non-experts vs. only 7% of experts said that running antivirus software was one of the top three three things they do to stay safe online. Experts acknowledged the benefits of antivirus software, but expressed concern that it might give users a false sense of security since it’s not a bulletproof solution.
In the immediate term, we encourage everyone to read the
full research paper
, borrow experts’ top practices, and also check out our tips for
keeping your information safe on Google
More broadly, our findings highlight fundamental misunderstandings about basic online security practices. Software updates, for example, are the seatbelts of online security; they make you safer, period. And yet, many non-experts not only overlook these as a best practice, but also mistakenly worry that software updates are a security risk.
No practice on either list—expert or non-expert—makes users less secure. But, there is clearly room to improve how security best practices are prioritized and communicated to the vast majority of (non expert) users. We’re looking forward to tackling that challenge.
Working Together to Filter Automated Data-Center Traffic
July 21, 2015
Posted by Vegard Johnsen, Product Manager Google Ad Traffic Quality
Trustworthy Accountability Group
a new pilot blacklist to protect advertisers across the industry. This blacklist comprises data-center IP addresses associated with non-human ad requests. We're happy to support this effort along with other industry leaders—Dstillery, Facebook, MediaMath, Quantcast, Rubicon Project, TubeMogul and Yahoo—and contribute our own data-center blacklist. As mentioned to
and in our recent
call to action
, we believe that if we work together we can raise the fraud-fighting bar for the whole industry.
Data-center traffic is one of
of non-human or illegitimate ad traffic. The newly shared blacklist identifies web robots or “bots” that are being run in data centers but that avoid detection by the
IAB/ABC International Spiders & Bots List
. Well-behaved bots announce that they're bots as they surf the web by including a bot identifier in their declared User-Agent strings. The bots filtered by this new blacklist are different. They masquerade as human visitors by using User-Agent strings that are indistinguishable from those of typical web browsers.
In this post, we take a closer look at a few examples of data-center traffic to show why it’s so important to filter this traffic across the industry.
Impact of the data-center blacklist
When observing the traffic generated by the IP addresses in the newly shared blacklist, we found significantly distorted click metrics. In May of 2015 on DoubleClick Campaign Manager alone, we found the blacklist filtered 8.9% of all clicks. Without filtering these clicks from campaign metrics, advertiser click-through rates would have been incorrect and for some advertisers this error would have been very large.
Below is a plot that shows how much click-through rates in May would have been inflated across the most impacted of DoubleClick Campaign Manager’s larger advertisers.
Two examples of bad data-center traffic
There are two distinct types of invalid data-center traffic: where the intent is malicious and where the impact on advertisers is accidental. In this section we consider two interesting examples where we’ve observed traffic that was likely generated with malicious intent.
Publishers use many different strategies to increase the traffic to their sites. Unfortunately, some are willing to use any means necessary to do so. In our investigations we’ve seen instances where publishers have been running software tools in data centers to intentionally mislead advertisers with fake impressions and fake clicks.
UrlSpirit is just one example of software that some unscrupulous publishers have been using to collaboratively drive automated traffic to their websites. Participating publishers install the UrlSpirit application on Windows machines and they each submit up to three URLs through the application’s interface. Submitted URLs are then distributed to other installed instances of the application, where Internet Explorer is used to automatically visit the list of target URLs. Publishers who have not installed the application can also leverage the network of installations by paying a fee.
At the end of May more than 82% of the UrlSpirit installations were being run on machines in data centers. There were more than 6,500 data-center installations of UrlSpirit, with each data-center installation running in a separate virtual machine. In aggregate, the data-center installations of UrlSpirit were generating a monthly rate of at least half a billion ad requests— an average of 2,500 fraudulent ad requests per installation per day.
HitLeap is another example of software that some publishers are using to collaboratively drive automated traffic to their websites. The software also runs on Windows machines, and each instance uses the Chromium Embedded Framework to automatically browse the websites of participating publishers—rather than using Internet Explorer.
Before publishers can use the network of installations to drive traffic to their websites, they need browsing minutes. Participating publishers earn browsing minutes by running the application on their computers. Alternatively, they can simply buy browsing minutes—with bundles starting at $9 for 10,000 minutes or up to 1,000,000 minutes for $625.
Publishers can specify as many target URLs as they like. The number of visits they receive from the network of installations is a function of how long they want the network of bots to spend on their sites. For example, ten browsing minutes will get a publisher five visits if the publisher requests two-minute visit durations.
In mid-June, at least 4,800 HitLeap installations were being run in virtual machines in data centers, with a unique IP associated with each HitLeap installation. The data-center installations of HitLeap made up 16% of the total HitLeap network, which was substantially larger than the UrlSpirit network.
In aggregate, the data-center installations of HitLeap were generating a monthly rate of at least a billion fraudulent ad requests—or an average of 1,600 ad requests per installation per day.
Not only were these publishers collectively responsible for billions of automated ad requests, but their websites were also often extremely deceptive. For example, of the top ten webpages visited by HitLeap bots in June, nine of these included
hidden ad slots
-- meaning that not only was the traffic fake, but the ads couldn’t have been seen even if they had been legitimate human visitors.
is illustrative of these nine webpages with hidden ad slots. The webpage has no visible content other than a single 300×250px ad. This visible ad is actually in a 300×250px iframe that includes two ads, the second of which is hidden. Additionally, there are also twenty-seven 0×0px hidden iframes on this page with each hidden iframe including two ad slots. In total there are fifty-five hidden ads on this page and one visible ad. Finally, the ads served on
appear to advertisers as though they have been served on legitimate websites like indiatimes.com, scotsman.com, autotrader.co.uk, allrecipes.com, dictionary.com and nypost.com, because the tags used on
to request the ad creatives have been deliberately spoofed.
An example of collateral damage
Unlike the traffic described above, there is also automated data-center traffic that impacts advertising campaigns but that hasn’t been generated for malicious purposes. An interesting example of this is an advertising competitive intelligence company that is generating a large volume of undeclared non-human traffic.
This company uses bots to scrape the web to find out which ad creatives are being served on which websites and at what scale. The company’s scrapers also click ad creatives to analyse the landing page destinations. To provide its clients with the most accurate possible intelligence, this company’s scrapers operate at extraordinary scale and they also do so without including bot identifiers in their User-Agent strings.
While the aim of this company is not to cause advertisers to pay for fake traffic, the company’s scrapers do waste advertiser spend. They not only generate non-human impressions; they also distort the metrics that advertisers use to evaluate campaign performance—in particular, click metrics. Looking at the data across DoubleClick Campaign Manager this company’s scrapers were responsible for 65% of the automated data-center clicks recorded in the month of May.
Google has always invested to prevent this and other types of invalid traffic from entering our ad platforms. By contributing our data-center blacklist to TAG, we hope to help others in the industry protect themselves.
We’re excited by the collaborative spirit we’ve seen working with other industry leaders on this initiative. This is an important, early step toward tackling fraudulent and illegitimate inventory across the industry and we look forward to sharing more in the future. By pooling our collective efforts and working with industry bodies, we can create strong defenses against those looking to take advantage of our ecosystem. We look forward to working with the TAG Anti-fraud working group to turn this pilot program into an industry-wide tool.
Google, the Wassenaar Arrangement, and vulnerability research
July 20, 2015
Neil Martin, Export Compliance Counsel,
Tim Willis, Hacker Philanthropist, Chrome Security Team
Cross-posted on the
Google Public Policy Blog
As the usage and complexity of software grows, the importance of security research has grown with it. It’s through diligent research that we uncover and fix bugs — like
— that can cause serious security issues for web users around the world.
The time and effort it takes to uncover bugs is significant, and the marketplace for these vulnerabilities is competitive. That’s why we provide cash rewards for quality security research that identifies problems in our own products or proactive improvements to open-source products. We’ve
more than $4 million to researchers from all around the world - our current Hall of Fame includes researchers from Germany, the U.S., Japan, Brazil, and more than 30 other countries.
Problematic new export controls
With the benefits of security research in mind, there has been some public
proposed export control rules
put forth by the U.S. Department of Commerce that would negatively affect vulnerability research.
The Commerce Department's proposed rules stem from U.S. membership in the
, a multilateral export control association. Members of the Wassenaar Arrangement have agreed to control a wide range of goods, software, and information, including technologies relating to "intrusion software" (as they've defined that term).
We believe that these proposed rules, as currently written, would have a significant negative impact on the open security research community. They would also hamper our ability to defend ourselves, our users, and make the web safer. It would be a disastrous outcome if an export regulation intended to make people more secure resulted in billions of users across the globe becoming persistently less secure.
Google comments on proposed rules
Earlier today, we formally submitted comments on the proposed rules to the United States Commerce Department’s Bureau of Industry and Security (BIS). Our comments are lengthy, but we wanted to share some of the main concerns and questions that we have officially expressed to the U.S. government today:
Rules are dangerously broad and vague.
The proposed rules are not feasible and would require Google to request thousands - maybe even tens of thousands - of export licenses. Since Google operates in many different countries, the controls could cover our communications about software vulnerabilities, including: emails, code review systems, bug tracking systems, instant messages - even some in-person conversations!
BIS’ own FAQ
states that information about a vulnerability, including its causes, wouldn’t be controlled, but we believe that it sometimes actually could be controlled information.
You should never need a license when you report a bug to get it fixed.
There should be standing license exceptions for everyone when controlled information is reported back to manufacturers for the purposes of fixing a vulnerability. This would provide protection for security researchers that report vulnerabilities, exploits, or other controlled information to any manufacturer or their agent.
Global companies should be able to share information globally.
If we have information about intrusion software, we should be able to share that with our engineers, no matter where they physically sit.
Clarity is crucial.
We acknowledge that we have a team of lawyers here to help us out, but navigating these controls shouldn’t be that complex and confusing. If BIS is going to implement the proposed controls, we recommend providing a simple, visual flowchart for everyone to easily understand when they need a license.
These controls should be changed ASAP.
The only way to fix the scope of the intrusion software controls is to do it at the annual meeting of Wassenaar Arrangement members in December 2015.
We’re committed to working with BIS to make sure that both white hat security researchers’ interests and Google users’ interests are front of mind. The proposed BIS rule for public comment is available
, and comments can also be sent directly to
. If BIS publishes another proposed rule on intrusion software, we’ll make sure to come back and update this blog post with details.
More Visible Protection Against Unwanted Software
July 16, 2015
Posted by Moheeb Abu Rajab and Stephan Somogyi, Google Safe Browsing Team
Last year, we announced our
increased focus on unwanted software (UwS)
published our unwanted software policy
. This work is the direct result of our users falling prey to UwS, and how badly it was affecting their browsing experience. Since then, Google Safe Browsing’s ability to detect deceptive software has steadily improved.
In the coming weeks, these detection improvements will become more noticeable in Chrome: users will see more
(like the one below) about unwanted software than ever before.
We want to be really clear that Google Safe Browsing’s mandate remains unchanged: we’re exclusively focused on protecting users from malware, phishing, unwanted software, and similar harm. You won’t see Safe Browsing warnings for any other reasons.
Unwanted software is being distributed on web sites via a variety of sources,
as well as ad networks lacking strict quality guidelines. In many cases, Safe Browsing within your browser is your last line of defense.
Google Safe Browsing has protected users from phishing and malware since 2006, and from unwanted software since 2014. We provide this protection across browsers (Chrome, Firefox, and Safari) and across platforms (Windows, Mac OS X, Linux, and Android). If you want to help us improve the defenses for everyone using a browser that integrates Safe Browsing, please consider checking the box that appears on all of our warning pages:
Safe Browsing’s focus is solely on protecting people and their data from badness. And nothing else.
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