Posted by Cesar Ghali and Julien Boeuf, Engineers on the Security & Privacy Team
At Google, protection of customer data is a top priority. One way we do this is by protecting data in transit by default. We protect data when it is sent to Google using secure communication protocols such as TLS (Transport Layer Security). Within our infrastructure, we protect service-to-service communications at the application layer using a system called Application Layer Transport Security (ALTS). ALTS authenticates the communication between Google services and helps protect data in transit. Today, we’re releasing a whitepaper, “Application Layer Transport Security,” that goes into detail about what ALTS is, how it protects data, and how it’s implemented at Google.

ALTS is a highly reliable, trusted system that provides authentication and security for our internal Remote Procedure Call (RPC) communications. ALTS requires minimal involvement from the services themselves. When services communicate with each other at Google, such as the Gmail frontend communicating with a storage backend system, they do not need to explicitly configure anything to ensure data transmission is protected - it is protected by default. All RPCs issued or received by a production workload that stay within a physical boundary controlled by or on behalf of Google are protected with ALTS by default. This delivers numerous benefits while allowing the system work at scale:

1. More precise security: Each workload has its own identity. This allows workloads running on the same machine to authenticate using their own identity as opposed to the machine’s identity.
2. Improved scalability: ALTS accommodates Google’s massive scale by using an efficient resumption mechanism embedded in the ALTS handshake protocol, allowing services that were already communicating to easily resume communications. ALTS can also accommodate the authentication and encryption needs of a large number of RPCs; for example, services running on Google production systems collectively issue on the order of O(1010) RPCs per second.
3. Reduced overhead: The overhead of potentially expensive cryptographic operations can be reduced by supporting long-lived RPC channels.

Posted by Paul Stanton and Brooke Heinichen, Safe Browsing Team

Updated on 12/14/17 to further distinguish between Unwanted Software Policy and Google Play Developer Program Policy
In our efforts to protect users and serve developers, the Google Safe Browsing team has expanded enforcement of Google's Unwanted Software Policy to further tamp down on unwanted and harmful mobile behaviors on Android. As part of this expanded enforcement, Google Safe Browsing will show warnings on apps and on websites leading to apps that collect a user’s personal data without their consent.

Apps handling personal user data (such as user phone number or email), or device data will be required to prompt users and to provide their own privacy policy in the app. Additionally, if an app collects and transmits personal data unrelated to the functionality of the app then, prior to collection and transmission, the app must prominently highlight how the user data will be used and have the user provide affirmative consent for such use.

These data collection requirements apply to all functions of the app. For example, during analytics and crash reportings, the list of installed packages unrelated to the app may not be transmitted from the device without prominent disclosure and affirmative consent.

These requirements, under the Unwanted Software Policy, apply to apps in Google Play and non-Play app markets. The Google Play team has also published guidelines for how Play apps should handle user data and provide disclosure.

Starting in 60 days, this expanded enforcement of Google’s Unwanted Software Policy may result in warnings shown on user devices via Google Play Protect or on webpages that lead to these apps. Webmasters whose sites show warnings due to distribution of these apps should refer to the Search Console for guidance on remediation and resolution of the warnings. Developers whose apps show warnings should refer to guidance in the Unwanted Software Help Center. Developers can also request an app review using this article on App verification and appeals, which contains guidance applicable to apps in both Google Play and non-Play app stores. Apps published in Google Play have specific criteria to meet under Google Play’s Developer Program Policies; these criteria are outlined in the Play August 2017 announcement.

Posted by Anthony Desnos, Megan Ruthven, and Richard Neal, Google Play Protect security engineers and Clement Lecigne, Threat Analysis Group

Google is constantly working to improve our systems that protect users from Potentially Harmful Applications (PHAs). Usually, PHA authors attempt to install their harmful apps on as many devices as possible. However, a few PHA authors spend substantial effort, time, and money to create and install their harmful app on a small number of devices to achieve a certain goal.

This blog post covers Tizi, a backdoor family with some rooting capabilities that was used in a targeted attack against devices in African countries, specifically: Kenya, Nigeria, and Tanzania. We'll talk about how the Google Play Protect and Threat Analysis teams worked together to detect and investigate Tizi-infected apps and remove and block them from Android devices.
What is Tizi?

Tizi is a fully featured backdoor that installs spyware to steal sensitive data from popular social media applications. The Google Play Protect security team discovered this family in September 2017 when device scans found an app with rooting capabilities that exploited old vulnerabilities. The team used this app to find more applications in the Tizi family, the oldest of which is from October 2015. The Tizi app developer also created a website and used social media to encourage more app installs from Google Play and third-party websites.

Here is an example social media post promoting a Tizi-infected app:

• Check permissions: Be cautious with apps that request unreasonable permissions. For example, a flashlight app shouldn't need access to send SMS messages.
• Enable a secure lock screen: Pick a PIN, pattern, or password that is easy for you to remember and hard for others to guess.
• Update your device: Keep your device up-to-date with the latest security patches. Tizi exploited older and publicly known security vulnerabilities, so devices that have up-to-date security patches are less exposed to this kind of attack.
• Google Play Protect: Ensure Google Play Protect is enabled.
• Locate your device: Practice finding your device, because you are far more likely to lose your device than install a PHA.

Posted by Xiaowen Xin, Android Security Team
The new Google Pixel 2 ships with a dedicated hardware security module designed to be robust against physical attacks. This hardware module performs lockscreen passcode verification and protects your lock screen better than software alone.

To learn more about the new protections, let’s first review the role of the lock screen. Enabling a lock screen protects your data, not just against casual thieves, but also against sophisticated attacks. Many Android devices, including all Pixel phones, use your lockscreen passcode to derive the key that is then used to encrypt your data. Before you unlock your phone for the first time after a reboot, an attacker cannot recover the key (and hence your data) without knowing your passcode first. To protect against brute-force guessing your passcode, devices running Android 7.0+ verify your attempts in a secure environment that limits how often you can repeatedly guess. Only when the secure environment has successfully verified your passcode does it reveal a device and user-specific secret used to derive the disk encryption key.

Benefits of tamper-resistant hardware

The goal of these protections is to prevent attackers from decrypting your data without knowing your passcode, but the protections are only as strong as the secure environment that verifies the passcode. Performing these types of security-critical operations in tamper-resistant hardware significantly increases the difficulty of attacking it.
Tamper-resistant hardware comes in the form of a discrete chip separate from the System on a Chip (SoC). It includes its own flash, RAM, and other resources inside a single package, so it can fully control its own execution. It can also detect and defend against outside attempts to physically tamper with it.

Posted by Kurt Thomas, Anti-Abuse Research; Angelika Moscicki, Account Security
Account takeover, or ‘hijacking’, is unfortunately a common problem for users across the web. More than 15% of Internet users have reported experiencing the takeover of an email or social networking account. However, despite its familiarity, there is a dearth of research about the root causes of hijacking.

With Google accounts as a case-study, we teamed up with the University of California, Berkeley to better understand how hijackers attempt to take over accounts in the wild. From March 2016 to March 2017, we analyzed several black markets to see how hijackers steal passwords and other sensitive data. We’ve highlighted some important findings from our investigation below. We presented our study at the Conference on Computer and Communications Security (CCS) and it’s now available here.

What we learned from the research proved to be immediately useful. We applied its insights to our existing protections and secured 67 million Google accounts before they were abused. We’re sharing this information publicly so that other online services can better secure their users, and can also supplement their authentication systems with more protections beyond just passwords.


How hijackers steal passwords on the black market

Our research tracked several black markets that traded third-party password breaches, as well as 25,000 blackhat tools used for phishing and keylogging. In total, these sources helped us identify 788,000 credentials stolen via keyloggers, 12 million credentials stolen via phishing, and 3.3 billion credentials exposed by third-party breaches.

While our study focused on Google, these password stealing tactics pose a risk to all account-based online services. In the case of third-party data breaches, 12% of the exposed records included a Gmail address serving as a username and a password; of those passwords, 7% were valid due to reuse. When it comes to phishing and keyloggers, attackers frequently target Google accounts to varying success: 12-25% of attacks yield a valid password.

However, because a password alone is rarely sufficient for gaining access to a Google account, increasingly sophisticated attackers also try to collect sensitive data that we may request when verifying an account holder’s identity. We found 82% of blackhat phishing tools and 74% of keyloggers attempted to collect a user’s IP address and location, while another 18% of tools collected phone numbers and device make and model.

By ranking the relative risk to users, we found that phishing posed the greatest threat, followed by keyloggers, and finally third-party breaches.

Protecting our users from account takeover

Our findings were clear: enterprising hijackers are constantly searching for, and are able to find, billions of different platforms’ usernames and passwords on black markets. While we have already applied these insights to our existing protections, our findings are yet another reminder that we must continuously evolve our defenses in order to stay ahead of these bad actors and keep users safe.

For many years, we’ve applied a ‘defense in-depth’ approach to security—a layered series of constantly improving protections that automatically prevent, detect, and mitigate threats to keep your account safe.

Prevention

A wide variety of safeguards help us to prevent attacks before they ever affect our users. For example, Safe Browsing, which now protects more than 3 billion devices, alerts users before they visit a dangerous site or when they click a link to a dangerous site within Gmail. We recently announced the Advanced Protection program which provides extra security for users that are at elevated risk of attack.

Detection

We monitor every login attempt to your account for suspicious activity. When there is a sign-in attempt from a device you’ve never used, or a location you don’t commonly access your account from, we’ll require additional information before granting access to your account. For example, if you sign in from a new laptop and you have a phone associated with you account, you will see a prompt—we’re calling these dynamic verification challenges—like this:
This challenge provides two-factor authentication on all suspicious logins, while mitigating the risk of account lockout.

Mitigation

Finally, we regularly scan activity across Google’s suite of products for suspicious actions performed by hijackers and when we find any, we lock down the affected accounts to prevent any further damage as quickly as possible. We prevent or undo actions we attribute to account takeover, notify the affected user, and help them change their password and re-secure their account into a healthy state.

What you can do

There are some simple steps you can take that make these defenses even stronger. Visit our Security Checkup to make sure you have recovery information associated with your account, like a phone number. Allow Chrome to automatically generate passwords for your accounts and save them via Smart Lock. We’re constantly working to improve these tools, and our automatic protections, to keep your data safe.

Posted by Renu Chaudhary, Android Security and Rahul Mishra, Program Manager

We have long enjoyed a close relationship with the security research community. To recognize the valuable external contributions that help us keep our users safe online, we maintain reward programs for Google-developed websites and apps, for Chrome and Chrome OS, and for the latest version of Android running on Pixel devices. These programs have been a success and helped uncover hundreds of vulnerabilities, while also paying out millions of dollars to participating security researchers and research teams.

Today, we’re introducing the Google Play Security Reward Program to incentivize security research into popular Android apps available on Google Play. Through our collaboration with independent bug bounty platform, HackerOne, we’ll enable security researchers to submit an eligible vulnerability to participating developers, who are listed in the program rules. After the vulnerability is addressed, the eligible researcher submits a report to the Play Security Reward Program to receive a monetary reward from Google Play.

With the ongoing success of our other reward programs, we invite developers and the research community to work together with us on proactively improving the security of some of the most popular Android apps on Google Play.

The program is limited to a select number of developers at this time to get initial feedback. Developers can contact their Google Play partner manager to show interest. All developers will benefit when bugs are discovered because we will scan all apps for them and deliver security recommendations to the developers of any affected apps. For more information, visit the Play Security Reward Program on HackerOne.

Posted by Fermin J. Serna, Staff Software Engineer, Matt Linton, Senior Security Engineer and Kevin Stadmeyer, Technical Program Manager

Our team has previously posted about DNS vulnerabilities and exploits. Lately, we’ve been busy reviewing the security of another DNS software package: Dnsmasq. We are writing this to disclose the issues we found and to publicize the patches in an effort to increase their uptake.

Dnsmasq provides functionality for serving DNS, DHCP, router advertisements and network boot. This software is commonly installed in systems as varied as desktop Linux distributions (like Ubuntu), home routers, and IoT devices. Dnsmasq is widely used both on the open internet and internally in private networks.

We discovered seven distinct issues (listed below) over the course of our regular internal security assessments. Once we determined the severity of these issues, we worked to investigate their impact and exploitability and then produced internal proofs of concept for each of them. We also worked with the maintainer of Dnsmasq, Simon Kelley, to produce appropriate patches and mitigate the issue.

These patches have been upstreamed and are now committed to the project’s git repository. In addition to these patches we have also submitted another patch which will run Dnsmasq under seccomp-bpf to allow for additional sandboxing. This patch has been submitted to the DNSmasq project for review and we have also made it available here for those who wish to integrate it into an existing install (after testing, of course!). We believe the adoption of this patch will increase the security of DNSMasq installations.

We would like to thank Simon Kelley for his help in patching these bugs in the core Dnsmasq codebase. Users who have deployed the latest version of Dnsmasq (2.78) will be protected from the attacks discovered here. Android partners have received this patch as well and it will be included in Android's monthly security update for October. Kubernetes versions 1.5.8, 1.6.11, 1.7.7, and 1.8.0 have been released with a patched DNS pod. Other affected Google services have been updated.

During our review, the team found three potential remote code executions, one information leak, and three denial of service vulnerabilities affecting the latest version at the project git server as of September 5th 2017.

CVE	Impact	Vector	Notes	PoC
CVE-2017-14491	RCE	DNS	Heap based overflow (2 bytes). Before 2.76 and this commit overflow was unrestricted.	PoC, instructions and ASAN report
CVE-2017-14492	RCE	DHCP	Heap based overflow.	PoC, instructions and ASAN report
CVE-2017-14493	RCE	DHCP	Stack Based overflow.	PoC, instructions and ASAN report
CVE-2017-14494	Information Leak	DHCP	Can help bypass ASLR.	PoC and Instructions
CVE-2017-14495	OOM/DoS	DNS	Lack of free() here.	PoC and  instructions
CVE-2017-14496	DoS	DNS	Invalid boundary checks here. Integer underflow leading to a huge memcpy.	PoC, instructions and ASAN report
CVE-2017-13704	DoS	DNS	Bug collision with CVE-2017-13704

It is worth expanding on some of these:

• CVE-2017-14491 is a DNS-based vulnerability that affects both directly exposed and internal network setups. Although the latest git version only allows a 2-byte overflow, this could be exploited based on previous research. Before version 2.76 and this commit the overflow is unrestricted. 

==1159==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x62200001dd0b at pc 0x0000005105e7 bp 0x7fff6165b9b0 sp0x7fff6165b9a8

Posted by Ben McIlwain, Google Registry
The security of the Web is of the utmost importance to Google. One of the most powerful tools in the Web security toolbox is ensuring that connections to websites are encrypted using HTTPS, which prevents Web traffic from being intercepted, altered, or misdirected in transit. We have taken many actions to make the use of HTTPS more widespread, both within Google and on the larger Internet.

We began in 2010 by defaulting to HTTPS for Gmail and starting the transition to encrypted search by default. In 2014, we started encouraging other websites to use HTTPS by giving secure sites a ranking boost in Google Search. In 2016, we became a platinum sponsor of Let’s Encrypt, a service that provides simple and free SSL certificates. Earlier this year we announced that Chrome will start displaying warnings on insecure sites, and we recently introduced fully managed SSL certificates in App Engine. And today we’re proud to announce that we are beginning to use another tool in our toolbox, the HTTPS Strict Transport Security (HSTS) preload list, in a new and more impactful way.

The HSTS preload list is built in to all major browsers (Chrome, Firefox, Safari, Internet Explorer/Edge, and Opera). It consists of a list of hostnames for which browsers automatically enforce HTTPS-secured connections. For example, gmail.com is on the list, which means that the aforementioned browsers will never make insecure connections to Gmail; if the user types http://gmail.com, the browser first changes it to https://gmail.com before sending the request. This provides greater security because the browser never loads an http-to-https redirect page, which could be intercepted.

The HSTS preload list can contain individual domains or subdomains and even top-level domains (TLDs), which are added through the HSTS website. The TLD is the last part of the domain name, e.g., .com, .net, or .org. Google operates 45 TLDs, including .google, .how, and .soy. In 2015 we created the first secure TLD when we added .google to the HSTS preload list, and we are now rolling out HSTS for a larger number of our TLDs, starting with .foo and .dev.

The use of TLD-level HSTS allows such namespaces to be secure by default. Registrants receive guaranteed protection for themselves and their users simply by choosing a secure TLD for their website and configuring an SSL certificate, without having to add individual domains or subdomains to the HSTS preload list. Moreover, since it typically takes months between adding a domain name to the list and browser upgrades reaching a majority of users, using an already-secured TLD provides immediate protection rather than eventual protection. Adding an entire TLD to the HSTS preload list is also more efficient, as it secures all domains under that TLD without the overhead of having to include all those domains individually.

We hope to make some of these secure TLDs available for registration soon, and would like to see TLD-wide HSTS become the security standard for new TLDs.

Updated 2017-10-06: To clear up some confusion in the responses to this post, we are not rolling out HSTS to Google's previously launched open TLDs (.how, .soy, and .みんな).

Posted by Stephan Somogyi, Safe Browsing Emeritus and Allison Miller, Security & Privacy

[Cross-posted from The Keyword]

In 2007, we launched Safe Browsing, one of Google’s earliest anti-malware efforts. To keep our users safe, we’d show them a warning before they visited a site that might’ve harmed their computers.
Computing has evolved a bit in the last decade, though. Smartphones created a more mobile internet, and now AI is increasingly changing how the world interacts with it. Safe Browsing also had to evolve to effectively protect users.

And it has: In May 2016, we announced that Safe Browsing was protecting more than 2 billion devices from badness on the internet. Today we’re announcing that Safe Browsing has crossed the threshold to 3 billion devices. We’re sharing a bit more about how we got here, and where we’re going.

What is Safe Browsing?

You may not know Safe Browsing by name, since most of the time we’re invisibly protecting you, without getting in the way. But you may have seen a warning like this at some point:
This notification is one of the visible parts of Safe Browsing, a collection of Google technologies that hunt badness—typically websites that deceive users—on the internet. We identify sites that might try to phish you, or sites that install malware or other undesirable software. The systems that make up Safe Browsing work together to identify, analyze and continuously keep Safe Browsing’s knowledge of the harmful parts of the internet up to date.

This protective information that we generate—a curated list of places that are dangerous for people and their devices—is used across many of our products. It helps keep search results safe and keep ads free from badness; it’s integral to Google Play Protect and keeps you safe on Android; and it helps Gmail shield you from malicious messages.

And Safe Browsing doesn’t protect only Google’s products. For many years, Safari and Firefox have protected their users with Safe Browsing as well. If you use an up-to-date version of Chrome, Firefox or Safari, you’re protected by default. Safe Browsing is also used widely by web developers and app developers (including Snapchat), who integrate our protections by checking URLs before they’re presented to their users.

Protecting more people with fewer bits

In the days when web browsers were used only on personal computers, we didn’t worry much about the amount of data Safe Browsing sent over the internet to keep your browser current. Mobile devices changed all that: Slow connections, expensive mobile data plans, and scarce battery capacity became important new considerations.

So over the last few years, we’ve rethought how Safe Browsing delivers data. We built new technologies to make its data as compact as possible: We only send the information that’s most protective to a given device, and we make sure this data is compressed as tightly as possible. (All this work benefits desktop browsers, too!)

We initially introduced our new mobile-optimized method in late 2015 with Chrome on Android, made it more broadly available in mid-2016, when we also started actively encouraging Android developers to integrate it. With the release of iOS 10 in September 2016, Safari began using our new, efficient Safe Browsing update technology, giving iOS users a protection boost.

Safe Browsing in an AI-first world

The internet is at the start of another major shift. Safe Browsing has already been using machine learning for many years to detect much badness of many kinds. We’re continually evaluating and integrating cutting-edge new approaches to improve Safe Browsing.

Protecting all users across all their platforms makes the internet safer for everyone. Wherever the future of the internet takes us, Safe Browsing will be there, continuing to evolve, expand, and protect people wherever they are.

Posted by Devon O’Brien, Ryan Sleevi, Andrew Whalley, Chrome Security

This post is a broader announcement of plans already finalized on the blink-dev mailing list.
Update, 1/31/18: Post was updated to further clarify 13 month validity limitations

At the end of July, the Chrome team and the PKI community converged upon a plan to reduce, and ultimately remove, trust in Symantec’s infrastructure in order to uphold users’ security and privacy when browsing the web. This plan, arrived at after significant debate on the blink-dev forum, would allow reasonable time for a transition to new, independently-operated Managed Partner Infrastructure while Symantec modernizes and redesigns its infrastructure to adhere to industry standards. This post reiterates this plan and includes a timeline detailing when site operators may need to obtain new certificates.

On January 19, 2017, a public posting to the mozilla.dev.security.policy newsgroup drew attention to a series of questionable website authentication certificates issued by Symantec Corporation’s PKI. Symantec’s PKI business, which operates a series of Certificate Authorities under various brand names, including Thawte, VeriSign, Equifax, GeoTrust, and RapidSSL, had issued numerous certificates that did not comply with the industry-developed CA/Browser Forum Baseline Requirements. During the subsequent investigation, it was revealed that Symantec had entrusted several organizations with the ability to issue certificates without the appropriate or necessary oversight, and had been aware of security deficiencies at these organizations for some time.

This incident, while distinct from a previous incident in 2015, was part of a continuing pattern of issues over the past several years that has caused the Chrome team to lose confidence in the trustworthiness of Symantec’s infrastructure, and as a result, the certificates that have been or will be issued from it.

After our agreed-upon proposal was circulated, Symantec announced the selection of DigiCert to run this independently-operated Managed Partner Infrastructure, as well as their intention to sell their PKI business to DigiCert in lieu of building a new trusted infrastructure. This post outlines the timeline for that transition and the steps that existing Symantec customers should take to minimize disruption to their users.

Information For Site Operators

Starting with Chrome 66, Chrome will remove trust in Symantec-issued certificates issued prior to June 1, 2016. Chrome 66 is currently scheduled to be released to Chrome Beta users on March 15, 2018 and to Chrome Stable users around April 17, 2018.

If you are a site operator with a certificate issued by a Symantec CA prior to June 1, 2016, then prior to the release of Chrome 66, you will need to replace the existing certificate with a new certificate from any Certificate Authority trusted by Chrome.

Additionally, by December 1, 2017, Symantec will transition issuance and operation of publicly-trusted certificates to DigiCert infrastructure, and certificates issued from the old Symantec infrastructure after this date will not be trusted in Chrome.

Around the week of October 23, 2018, Chrome 70 will be released, which will fully remove trust in Symantec’s old infrastructure and all of the certificates it has issued. This will affect any certificate chaining to Symantec roots, except for the small number issued by the independently-operated and audited subordinate CAs previously disclosed to Google.

Site operators that need to obtain certificates from Symantec’s existing root and intermediate certificates may do so from the old infrastructure until December 1, 2017, although these certificates will need to be replaced again prior to Chrome 70. Additionally, certificates issued using validation information from Symantec’s infrastructure will have their validity limited to 13 months. Alternatively, site operators may obtain replacement certificates from any other Certificate Authority currently trusted by Chrome, which are unaffected by this distrust or validity period limit.
Reference Timeline

The following is a timeline of relevant dates associated with this plan, which distills the various requirements and milestones into an actionable set of information for site operators. As always, Chrome release dates can vary by a number of days, but upcoming release dates can be tracked here.

Posted by Megan Ruthven Android Security, Ken Bodzak Threat Analysis Group, Neel Mehta Threat Analysis Group

Android Security is always developing new ways of using data to find and block potentially harmful apps (PHAs) from getting onto your devices. Earlier this year, we announced we had blocked Chrysaor targeted spyware, believed to be written by NSO Group, a cyber arms company. In the course of our Chrysaor investigation, we used similar techniques to discover a new and unrelated family of spyware called Lipizzan. Lipizzan’s code contains references to a cyber arms company, Equus Technologies.

Lipizzan is a multi-stage spyware product capable of monitoring and exfiltrating a user’s email, SMS messages, location, voice calls, and media. We have found 20 Lipizzan apps distributed in a targeted fashion to fewer than 100 devices in total and have blocked the developers and apps from the Android ecosystem. Google Play Protect has notified all affected devices and removed the Lipizzan apps.

We’ve enhanced Google Play Protect’s capabilities to detect the targeted spyware used here and will continue to use this framework to block more targeted spyware. To learn more about the methods Google uses to find targeted mobile spyware like Chrysaor and Lipizzan, attend our BlackHat talk, Fighting Targeted Malware in the Mobile Ecosystem.

How does Lipizzan work?

Getting on a target device

Lipizzan was a sophisticated two stage spyware tool. The first stage found by Google Play Protect was distributed through several channels, including Google Play, and typically impersonated an innocuous-sounding app such as a "Backup” or “Cleaner” app. Upon installation, Lipizzan would download and load a second "license verification" stage, which would survey the infected device and validate certain abort criteria. If given the all-clear, the second stage would then root the device with known exploits and begin to exfiltrate device data to a Command & Control server.

Once implanted on a target device

The Lipizzan second stage was capable of performing and exfiltrating the results of the following tasks:

• Call recording
• VOIP recording
• Recording from the device microphone
• Location monitoring
• Taking screenshots
• Taking photos with the device camera(s)
• Fetching device information and files
• Fetching user information (contacts, call logs, SMS, application-specific data)

The PHA had specific routines to retrieve data from each of the following apps:

• Gmail
• Hangouts
• KakaoTalk
• LinkedIn
• Messenger
• Skype
• Snapchat
• StockEmail
• Telegram
• Threema
• Viber
• Whatsapp

We saw all of this behavior on a standalone stage 2 app, com.android.mediaserver (not related to Android MediaServer). This app shared a signing certificate with one of the stage 1 applications, com.app.instantbackup, indicating the same author wrote the two. We could use the following code snippet from the 2nd stage (com.android.mediaserver) to draw ties to the stage 1 applications.



Morphing first stage

After we blocked the first set of apps on Google Play, new apps were uploaded with a similar format but had a couple of differences.

The apps changed from ‘backup’ apps to looking like a “cleaner”, “notepad”, “sound recorder”, and “alarm manager” app. The new apps were uploaded within a week of the takedown, showing that the authors have a method of easily changing the branding of the implant apps.
The app changed from downloading an unencrypted stage 2 to including stage 2 as an encrypted blob. The new stage 1 would only decrypt and load the 2nd stage if it received an intent with an AES key and IV.

Despite changing the type of app and the method to download stage 2, we were able to catch the new implant apps soon after upload.

How many devices were affected?

There were fewer than 100 devices that checked into Google Play Protect with the apps listed below. That means the family affected only 0.000007% of Android devices. Since we identified Lipizzan, Google Play Protect removed Lipizzan from affected devices and actively blocks installs on new devices.

What can you do to protect yourself?

• Ensure you are opted into Google Play Protect. 
• Exclusively use the Google Play store. The chance you will install a PHA is much lower on Google Play than using other install mechanisms.
• Keep “unknown sources” disabled while not using it.
• Keep your phone patched to the latest Android security update.

List of samples

1st stage



Standalone 2nd stage