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Android Protected Confirmation: Taking transaction security to the next level

19 Říjen, 2018 - 19:08
Posted by Janis Danisevskis, Information Security Engineer, Android Security

[Cross-posted from the Android Developers Blog]

In Android Pie, we introduced Android Protected Confirmation, the first major mobile OS API that leverages a hardware protected user interface (Trusted UI) to perform critical transactions completely outside the main mobile operating system. This Trusted UI protects the choices you make from fraudulent apps or a compromised operating system. When an app invokes Protected Confirmation, control is passed to the Trusted UI, where transaction data is displayed and user confirmation of that data's correctness is obtained.
Once confirmed, your intention is cryptographically authenticated and unforgeable when conveyed to the relying party, for example, your bank. Protected Confirmation increases the bank's confidence that it acts on your behalf, providing a higher level of protection for the transaction.
Protected Confirmation also adds additional security relative to other forms of secondary authentication, such as a One Time Password or Transaction Authentication Number. These mechanisms can be frustrating for mobile users and also fail to protect against a compromised device that can corrupt transaction data or intercept one-time confirmation text messages.
Once the user approves a transaction, Protected Confirmation digitally signs the confirmation message. Because the signing key never leaves the Trusted UI's hardware sandbox, neither app malware nor a compromised operating system can fool the user into authorizing anything. Protected Confirmation signing keys are created using Android's standard AndroidKeyStore API. Before it can start using Android Protected Confirmation for end-to-end secure transactions, the app must enroll the public KeyStore key and its Keystore Attestation certificate with the remote relying party. The attestation certificate certifies that the key can only be used to sign Protected Confirmations.
There are many possible use cases for Android Protected Confirmation. At Google I/O 2018, the What's new in Android security session showcased partners planning to leverage Android Protected Confirmation in a variety of ways, including Royal Bank of Canada person to person money transfers; Duo Security, Nok Nok Labs, and ProxToMe for user authentication; and Insulet Corporation and Bigfoot Biomedical, for medical device control.
Insulet, a global leading manufacturer of tubeless patch insulin pumps, has demonstrated how they can modify their FDA cleared Omnipod DASH TM Insulin management system in a test environment to leverage Protected Confirmation to confirm the amount of insulin to be injected. This technology holds the promise for improved quality of life and reduced cost by enabling a person with diabetes to leverage their convenient, familiar, and secure smartphone for control rather than having to rely on a secondary, obtrusive, and expensive remote control device. (Note: The Omnipod DASH™ System is not cleared for use with Pixel 3 mobile device or Protected Confirmation).

This work is fulfilling an important need in the industry. Since smartphones do not fit the mold of an FDA approved medical device, we've been working with FDA as part of DTMoSt, an industry-wide consortium, to define a standard for phones to safely control medical devices, such as insulinSince smartphones do not fit the mold of an FDA approved medical device, we've been working with FDA as part of DTMoSt, an industry-wide consortium, to define a standard for phones to safely control medical devices, such as insulin pumps. A technology like Protected Confirmation plays an important role in gaining higher assurance of user intent and medical safety.
To integrate Protected Confirmation into your app, check out the Android Protected Confirmation training article. Android Protected Confirmation is an optional feature in Android Pie. Because it has low-level hardware dependencies, Protected Confirmation may not be supported by all devices running Android Pie. Google Pixel 3 and 3XL devices are the first to support Protected Confirmation, and we are working closely with other manufacturers to adopt this market-leading security innovation on more devices.
Kategorie: Hacking & Security

Distrust of the Symantec PKI: Immediate action needed by site operators

17 Říjen, 2018 - 23:10
Posted by Devon O’Brien, Ryan Sleevi, Emily Stark, Chrome security team

Update October 17, 2018Chrome 70 has now been released to the Stable Channel, and users will start to see full screen interstitials on sites which still use certificates issues by the Legacy Symantec PKI. Initially this change will reach a small percentage of users, and then slowly scale up to 100% over the next several weeks.

Site Operators receiving problem reports from users are strongly encouraged to take corrective action by replacing their website certificates as soon as possible. Instructions on how to determine whether your site is affected as well as what corrective action is needed can be found below.


We previously announced plans to deprecate Chrome’s trust in the Symantec certificate authority (including Symantec-owned brands like Thawte, VeriSign, Equifax, GeoTrust, and RapidSSL). This post outlines how site operators can determine if they’re affected by this deprecation, and if so, what needs to be done and by when. Failure to replace these certificates will result in site breakage in upcoming versions of major browsers, including Chrome.

Chrome 66

If your site is using a SSL/TLS certificate from Symantec that was issued before June 1, 2016, it will stop functioning in Chrome 66, which could already be impacting your users.
If you are uncertain about whether your site is using such a certificate, you can preview these changes in Chrome Canary to see if your site is affected. If connecting to your site displays a certificate error or a warning in DevTools as shown below, you’ll need to replace your certificate. You can get a new certificate from any trusted CA, including Digicert, which recently acquired Symantec’s CA business.
An example of a certificate error that Chrome 66 users might see if you are using a Legacy Symantec SSL/TLS certificate that was issued before June 1, 2016. 

The DevTools message you will see if you need to replace your certificate before Chrome 66.Chrome 66 has already been released to the Canary and Dev channels, meaning affected sites are already impacting users of these Chrome channels. If affected sites do not replace their certificates by March 15, 2018, Chrome Beta users will begin experiencing the failures as well. You are strongly encouraged to replace your certificate as soon as possible if your site is currently showing an error in Chrome Canary.
Chrome 70
Starting in Chrome 70, all remaining Symantec SSL/TLS certificates will stop working, resulting in a certificate error like the one shown above. To check if your certificate will be affected, visit your site in Chrome today and open up DevTools. You’ll see a message in the console telling you if you need to replace your certificate.


The DevTools message you will see if you need to replace your certificate before Chrome 70.If you see this message in DevTools, you’ll want to replace your certificate as soon as possible. If the certificates are not replaced, users will begin seeing certificate errors on your site as early as July 20, 2018. The first Chrome 70 Beta release will be around September 13, 2018.
Expected Chrome Release Timeline
The table below shows the First Canary, First Beta and Stable Release for Chrome 66 and 70. The first impact from a given release will coincide with the First Canary, reaching a steadily widening audience as the release hits Beta and then ultimately Stable. Site operators are strongly encouraged to make the necessary changes to their sites before the First Canary release for Chrome 66 and 70, and no later than the corresponding Beta release dates.ReleaseFirst CanaryFirst BetaStable ReleaseChrome 66January 20, 2018~ March 15, 2018~ April 17, 2018Chrome 70~ July 20, 2018~ September 13, 2018~ October 16, 2018
For information about the release timeline for a particular version of Chrome, you can also refer to the Chromium Development Calendar which will be updated should release schedules change.
In order to address the needs of certain enterprise users, Chrome will also implement an Enterprise Policy that allows disabling the Legacy Symantec PKI distrust starting with Chrome 66. As of January 1, 2019, this policy will no longer be available and the Legacy Symantec PKI will be distrusted for all users. See this Enterprise Help Center article for more information.

Special Mention: Chrome 65
As noted in the previous announcement, SSL/TLS certificates from the Legacy Symantec PKI issued after December 1, 2017 are no longer trusted. This should not affect most site operators, as it requires entering in to special agreement with DigiCert to obtain such certificates. Accessing a site serving such a certificate will fail and the request will be blocked as of Chrome 65. To avoid such errors, ensure that such certificates are only served to legacy devices and not to browsers such as Chrome.
Kategorie: Hacking & Security

Modernizing Transport Security

17 Říjen, 2018 - 22:20
Posted by David Benjamin, Chrome networking

*Updated on October 17, 2018 with details about changes in other browsers

TLS (Transport Layer Security) is the protocol which secures HTTPS. It has a long history stretching back to the nearly twenty-year-old TLS 1.0 and its even older predecessor, SSL. Over that time, we have learned a lot about how to build secure protocols.

TLS 1.2 was published ten years ago to address weaknesses in TLS 1.0 and 1.1 and has enjoyed wide adoption since then. Today only 0.5% of HTTPS connections made by Chrome use TLS 1.0 or 1.1. These old versions of TLS rely on MD5 and SHA-1, both now broken, and contain other flaws. TLS 1.0 is no longer PCI-DSS compliant and the TLS working group has adopted a document to deprecate TLS 1.0 and TLS 1.1.

In line with these industry standards, Google Chrome will deprecate TLS 1.0 and TLS 1.1 in Chrome 72. Sites using these versions will begin to see deprecation warnings in the DevTools console in that release. TLS 1.0 and 1.1 will be disabled altogether in Chrome 81. This will affect users on early release channels starting January 2020. Apple, Microsoft, and Mozilla have made similar announcements.

Site administrators should immediately enable TLS 1.2 or later. Depending on server software (such as Apache or nginx), this may be a configuration change or a software update. Additionally, we encourage all sites to revisit their TLS configuration. Chrome’s current criteria for modern TLS is the following:

  • TLS 1.2 or later.
  • An ECDHE- and AEAD-based cipher suite. AEAD-based cipher suites are those using AES-GCM or ChaCha20-Poly1305. ECDHE_RSA_WITH_AES_128_GCM_SHA256 is the recommended option for most sites.
  • The server signature should use SHA-2. Note this is not the signature in the certificate, made by the CA. Rather, it is the signature made by the server itself, using its private key.

The older options—CBC-mode cipher suites, RSA-encryption key exchange, and SHA-1 online signatures—all have known cryptographic flaws. Each has been removed in the newly-published TLS 1.3, which is supported in Chrome 70. We retain them at prior versions for compatibility with legacy servers, but we will be evaluating them over time for eventual deprecation.

None of these changes require obtaining a new certificate. Additionally, they are backwards-compatible. Where necessary, servers may enable both modern and legacy options, to continue to support legacy clients. Note, however, such support may carry security risks. (For example, see the DROWN, FREAK, and ROBOT attacks.)

Over the coming Chrome releases, we will improve the DevTools Security Panel to point out deviations from these settings, and suggest improvements to the site’s configuration.

Enterprise deployments can preview the TLS 1.0 and 1.1 removal today by setting the SSLVersionMin policy to “tls1.2”. For enterprise deployments that need more time, this same policy can be used to re-enable TLS 1.0 or TLS 1.1 until January 2021.
Kategorie: Hacking & Security

Building a Titan: Better security through a tiny chip

17 Říjen, 2018 - 20:10

Posted by Nagendra Modadugu and Bill Richardson, Google Device Security Group

[Cross-posted from the Android Developers Blog]

At the Made by Google event last week, we talked about the combination of AI + Software + Hardware to help organize your information. To better protect that information at a hardware level, our new Pixel 3 and Pixel 3 XL devices include a Titan M chip.We briefly introduced Titan M and some of its benefits on our Keyword Blog, and with this post we dive into some of its technical details.
Titan M is a second-generation, low-power security module designed and manufactured by Google, and is a part of the Titan family. As described in the Keyword Blog post, Titan M performs several security sensitive functions, including:
  • Storing and enforcing the locks and rollback counters used by Android Verified Boot.
  • Securely storing secrets and rate-limiting invalid attempts at retrieving them using the Weaver API.
  • Providing backing for the Android Strongbox Keymaster module, including Trusted User Presence and Protected Confirmation. Titan M has direct electrical connections to the Pixel's side buttons, so a remote attacker can't fake button presses. These features are available to third-party apps, such as FIDO U2F Authentication.
  • Enforcing factory-reset policies, so that lost or stolen phones can only be restored to operation by the authorized owner.
  • Ensuring that even Google can't unlock a phone or install firmware updates without the owner's cooperation with Insider Attack Resistance.
Including Titan M in Pixel 3 devices substantially reduces the attack surface. Because Titan M is a separate chip, the physical isolation mitigates against entire classes of hardware-level exploits such as Rowhammer, Spectre, and Meltdown. Titan M's processor, caches, memory, and persistent storage are not shared with the rest of the phone's system, so side channel attacks like these—which rely on subtle, unplanned interactions between internal circuits of a single component—are nearly impossible. In addition to its physical isolation, the Titan M chip contains many defenses to protect against external attacks.
But Titan M is not just a hardened security microcontroller, but rather a full-lifecycle approach to security with Pixel devices in mind. Titan M's security takes into consideration all the features visible to Android down to the lowest level physical and electrical circuit design and extends beyond each physical device to our supply chain and manufacturing processes. At the physical level, we incorporated essential features optimized for the mobile experience: low power usage, low-latency, hardware crypto acceleration, tamper detection, and secure, timely firmware updates. We improved and invested in the supply chain for Titan M by creating a custom provisioning process, which provides us with transparency and control starting from the earliest silicon stages.
Finally, in the interest of transparency, the Titan M firmware source code will be publicly available soon. While Google holds the root keys necessary to sign Titan M firmware, it will be possible to reproduce binary builds based on the public source for the purpose of binary transparency.
A closer look at Titan MTitan (left) and Titan M (right)
Titan M's CPU is an ARM Cortex-M3 microprocessor specially hardened against side-channel attacks and augmented with defensive features to detect and respond to abnormal conditions. The Titan M CPU core also exposes several control registers, which can be used to taper access to chip configuration settings and peripherals. Once powered on, Titan M verifies the signature of its flash-based firmware using a public key built into the chip's silicon. If the signature is valid, the flash is locked so it can't be modified, and then the firmware begins executing.
Titan M also features several hardware accelerators: AES, SHA, and a programmable big number coprocessor for public key algorithms. These accelerators are flexible and can either be initialized with keys provided by firmware or with chip-specific and hardware-bound keys generated by the Key Manager module. Chip-specific keys are generated internally based on entropy derived from the True Random Number Generator (TRNG), and thus such keys are never externally available outside the chip over its entire lifetime.
While implementing Titan M firmware, we had to take many system constraints into consideration. For example, packing as many security features into Titan M's 64 Kbytes of RAM required all firmware to execute exclusively off the stack. And to reduce flash-wear, RAM contents can be preserved even during low-power mode when most hardware modules are turned off.
The diagram below provides a high-level view of the chip components described here.

Better security through transparency and innovationAt the heart of our implementation of Titan M are two broader trends: transparency and building a platform for future innovation.
Transparency around every step of the design process — from logic gates to boot code to the applications — gives us confidence in the defenses we're providing for our users. We know what's inside, how it got there, how it works, and who can make changes.
Custom hardware allows us to provide new features, capabilities, and performance not readily available in off-the-shelf components. These changes allow higher assurance use cases like two-factor authentication, medical device control, P2P payments, and others that we will help develop down the road.
As more of our lives are bound up in our phones, keeping those phones secure and trustworthy is increasingly important. Google takes that responsibility seriously. Titan M is just the latest step in our continuing efforts to improve the privacy and security of all our users.
Kategorie: Hacking & Security

Google and Android have your back by protecting your backups

12 Říjen, 2018 - 22:01
Posted by Troy Kensinger, Technical Program Manager, Android Security and Privacy

Android is all about choice. As such, Android strives to provide users many options to protect their data. By combining Android’s Backup Service and Google Cloud’s Titan Technology, Android has taken additional steps to securing users' data while maintaining their privacy.

Starting in Android Pie, devices can take advantage of a new capability where backed-up application data can only be decrypted by a key that is randomly generated at the client. This decryption key is encrypted using the user's lockscreen PIN/pattern/passcode, which isn’t known by Google. Then, this passcode-protected key material is encrypted to a Titan security chip on our datacenter floor. The Titan chip is configured to only release the backup decryption key when presented with a correct claim derived from the user's passcode. Because the Titan chip must authorize every access to the decryption key, it can permanently block access after too many incorrect attempts at guessing the user’s passcode, thus mitigating brute force attacks. The limited number of incorrect attempts is strictly enforced by a custom Titan firmware that cannot be updated without erasing the contents of the chip. By design, this means that no one (including Google) can access a user's backed-up application data without specifically knowing their passcode.

To increase our confidence that this new technology securely prevents anyone from accessing users' backed-up application data, the Android Security & Privacy team hired global cyber security and risk mitigation expert NCC Group to complete a security audit. Some of the outcomes included positives around Google’s security design processes, validation of code quality, and that mitigations for known attack vectors were already taken into account prior to launching the service. While there were some issues discovered during this audit, engineers corrected them quickly. For more details on how the end-to-end service works and a detailed report of NCC Group’s findings, click here.

Getting external reviews of our security efforts is one of many ways that Google and Android maintain transparency and openness which in turn helps users feel safe when it comes to their data. Whether it’s 100s of hours of gaming data or your personalized preferences in your favorite Google apps, our users' information is protected.

We want to acknowledge contributions from Shabsi Walfish, Software Engineering Lead, Identity and Authentication to this effort
Kategorie: Hacking & Security

Control Flow Integrity in the Android kernel

12 Říjen, 2018 - 15:28

Posted by Sami Tolvanen, Staff Software Engineer, Android Security & Privacy

[Cross-posted from the Android Developers Blog]

Android's security model is enforced by the Linux kernel, which makes it a tempting target for attackers. We have put a lot of effort into hardening the kernel in previous Android releases and in Android 9, we continued this work by focusing on compiler-based security mitigations against code reuse attacks.
Google's Pixel 3 will be the first Android device to ship with LLVM's forward-edge Control Flow Integrity (CFI) enforcement in the kernel, and we have made CFI support available in Android kernel versions 4.9 and 4.14. This post describes how kernel CFI works and provides solutions to the most common issues developers might run into when enabling the feature.
Protecting against code reuse attacksA common method of exploiting the kernel is using a bug to overwrite a function pointer stored in memory, such as a stored callback pointer or a return address that had been pushed to the stack. This allows an attacker to execute arbitrary parts of the kernel code to complete their exploit, even if they cannot inject executable code of their own. This method of gaining code execution is particularly popular with the kernel because of the huge number of function pointers it uses, and the existing memory protections that make code injection more challenging.
CFI attempts to mitigate these attacks by adding additional checks to confirm that the kernel's control flow stays within a precomputed graph. This doesn't prevent an attacker from changing a function pointer if a bug provides write access to one, but it significantly restricts the valid call targets, which makes exploiting such a bug more difficult in practice.

Figure 1. In an Android device kernel, LLVM's CFI limits 55% of indirect calls to at most 5 possible targets and 80% to at most 20 targets.Gaining full program visibility with Link Time Optimization (LTO)In order to determine all valid call targets for each indirect branch, the compiler needs to see all of the kernel code at once. Traditionally, compilers work on a single compilation unit (source file) at a time and leave merging the object files to the linker. LLVM's solution to CFI is to require the use of LTO, where the compiler produces LLVM-specific bitcode for all C compilation units, and an LTO-aware linker uses the LLVM back-end to combine the bitcode and compile it into native code.

Figure 2. A simplified overview of how LTO works in the kernel. All LLVM bitcode is combined, optimized, and generated into native code at link time.Linux has used the GNU toolchain for assembling, compiling, and linking the kernel for decades. While we continue to use the GNU assembler for stand-alone assembly code, LTO requires us to switch to LLVM's integrated assembler for inline assembly, and either GNU gold or LLVM's own lld as the linker. Switching to a relatively untested toolchain on a huge software project will lead to compatibility issues, which we have addressed in our arm64 LTO patch sets for kernel versions 4.9 and 4.14.
In addition to making CFI possible, LTO also produces faster code due to global optimizations. However, additional optimizations often result in a larger binary size, which may be undesirable on devices with very limited resources. Disabling LTO-specific optimizations, such as global inlining and loop unrolling, can reduce binary size by sacrificing some of the performance gains. When using GNU gold, the aforementioned optimizations can be disabled with the following additions to LDFLAGS:
LDFLAGS += -plugin-opt=-inline-threshold=0 \
-plugin-opt=-unroll-threshold=0Note that flags to disable individual optimizations are not part of the stable LLVM interface and may change in future compiler versions.
Implementing CFI in the Linux kernelLLVM's CFI implementation adds a check before each indirect branch to confirm that the target address points to a valid function with a correct signature. This prevents an indirect branch from jumping to an arbitrary code location and even limits the functions that can be called. As C compilers do not enforce similar restrictions on indirect branches, there were several CFI violations due to function type declaration mismatches even in the core kernel that we have addressed in our CFI patch sets for kernels 4.9 and 4.14.
Kernel modules add another complication to CFI, as they are loaded at runtime and can be compiled independently from the rest of the kernel. In order to support loadable modules, we have implemented LLVM's cross-DSO CFI support in the kernel, including a CFI shadow that speeds up cross-module look-ups. When compiled with cross-DSO support, each kernel module contains information about valid local branch targets, and the kernel looks up information from the correct module based on the target address and the modules' memory layout.

Figure 3. An example of a cross-DSO CFI check injected into an arm64 kernel. Type information is passed in X0 and the target address to validate in X1.CFI checks naturally add some overhead to indirect branches, but due to more aggressive optimizations, our tests show that the impact is minimal, and overall system performance even improved 1-2% in many cases.
Enabling kernel CFI for an Android deviceCFI for arm64 requires clang version >= 5.0 and binutils >= 2.27. The kernel build system also assumes that the LLVMgold.so plug-in is available in LD_LIBRARY_PATH. Pre-built toolchain binaries for clang and binutils are available in AOSP, but upstream binaries can also be used.
The following kernel configuration options are needed to enable kernel CFI:
CONFIG_LTO_CLANG=y
CONFIG_CFI_CLANG=yUsing CONFIG_CFI_PERMISSIVE=y may also prove helpful when debugging a CFI violation or during device bring-up. This option turns a violation into a warning instead of a kernel panic.
As mentioned in the previous section, the most common issue we ran into when enabling CFI on Pixel 3 were benign violations caused by function pointer type mismatches. When the kernel runs into such a violation, it prints out a runtime warning that contains the call stack at the time of the failure, and the call target that failed the CFI check. Changing the code to use a correct function pointer type fixes the issue. While we have fixed all known indirect branch type mismatches in the Android kernel, similar problems may be still found in device specific drivers, for example.
CFI failure (target: [<fffffff3e83d4d80>] my_target_function+0x0/0xd80):
------------[ cut here ]------------
kernel BUG at kernel/cfi.c:32!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP

Call trace:

[<ffffff8752d00084>] handle_cfi_failure+0x20/0x28
[<ffffff8752d00268>] my_buggy_function+0x0/0x10
…Figure 4. An example of a kernel panic caused by a CFI failure.Another potential pitfall are address space conflicts, but this should be less common in driver code. LLVM's CFI checks only understand kernel virtual addresses and any code that runs at another exception level or makes an indirect call to a physical address will result in a CFI violation. These types of failures can be addressed by disabling CFI for a single function using the __nocfi attribute, or even disabling CFI for entire code files using the $(DISABLE_CFI) compiler flag in the Makefile.
static int __nocfi address_space_conflict()
{
void (*fn)(void);

/* branching to a physical address trips CFI w/o __nocfi */
fn = (void *)__pa_symbol(function_name);
cpu_install_idmap();
fn();
cpu_uninstall_idmap();

}Figure 5. An example of fixing a CFI failure caused by an address space conflict.Finally, like many hardening features, CFI can also be tripped by memory corruption errors that might otherwise result in random kernel crashes at a later time. These may be more difficult to debug, but memory debugging tools such as KASAN can help here.
ConclusionWe have implemented support for LLVM's CFI in Android kernels 4.9 and 4.14. Google's Pixel 3 will be the first Android device to ship with these protections, and we have made the feature available to all device vendors through the Android common kernel. If you are shipping a new arm64 device running Android 9, we strongly recommend enabling kernel CFI to help protect against kernel vulnerabilities.
LLVM's CFI protects indirect branches against attackers who manage to gain access to a function pointer stored in kernel memory. This makes a common method of exploiting the kernel more difficult. Our future work involves also protecting function return addresses from similar attacks using LLVM's Shadow Call Stack, which will be available in an upcoming compiler release.
Kategorie: Hacking & Security

Trustworthy Chrome Extensions, by Default

1 Říjen, 2018 - 20:51
Posted by James Wagner, Chrome Extensions Product Manager

[Cross-posted from the Chromium blog]

Incredibly, it’s been nearly a decade since we launched the Chrome extensions system. Thanks to the hard work and innovation of our developer community, there are now more than 180,000 extensions in the Chrome Web Store, and nearly half of Chrome desktop users actively use extensions to customize Chrome and their experience on the web.

The extensions team's dual mission is to help users tailor Chrome’s functionality to their individual needs and interests, and to empower developers to build rich and useful extensions. But, first and foremost, it’s crucial that users be able to trust the extensions they install are safe, privacy-preserving, and performant. Users should always have full transparency about the scope of their extensions’ capabilities and data access.

We’ve recently taken a number of steps toward improved extension security with the launch of out-of-process iframes, the removal of inline installation, and significant advancements in our ability to detect and block malicious extensions using machine learning. Looking ahead, there are more fundamental changes needed so that all Chrome extensions are trustworthy by default.

Today we’re announcing some upcoming changes and plans for the future:

User controls for host permissions

Beginning in Chrome 70, users will have the choice to restrict extension host access to a custom list of sites, or to configure extensions to require a click to gain access to the current page.


While host permissions have enabled thousands of powerful and creative extension use cases, they have also led to a broad range of misuse - both malicious and unintentional - because they allow extensions to automatically read and change data on websites. Our aim is to improve user transparency and control over when extensions are able to access site data. In subsequent milestones, we’ll continue to optimize the user experience toward this goal while improving usability. If your extension requests host permissions, we encourage you to review our transition guide and begin testing as soon as possible.

Changes to the extensions review process

Going forward, extensions that request powerful permissions will be subject to additional compliance review. We’re also looking very closely at extensions that use remotely hosted code, with ongoing monitoring. Your extension’s permissions should be as narrowly-scoped as possible, and all your code should be included directly in the extension package, to minimize review time.
New code reliability requirements

Starting today, Chrome Web Store will no longer allow extensions with obfuscated code. This includes code within the extension package as well as any external code or resource fetched from the web. This policy applies immediately to all new extension submissions. Existing extensions with obfuscated code can continue to submit updates over the next 90 days, but will be removed from the Chrome Web Store in early January if not compliant.

Today over 70% of malicious and policy violating extensions that we block from Chrome Web Store contain obfuscated code. At the same time, because obfuscation is mainly used to conceal code functionality, it adds a great deal of complexity to our review process. This is no longer acceptable given the aforementioned review process changes.

Additionally, since JavaScript code is always running locally on the user's machine, obfuscation is insufficient to protect proprietary code from a truly motivated reverse engineer. Obfuscation techniques also come with hefty performance costs such as slower execution and increased file and memory footprints.

Ordinary minification, on the other hand, typically speeds up code execution as it reduces code size, and is much more straightforward to review. Thus, minification will still be allowed, including the following techniques:

  • Removal of whitespace, newlines, code comments, and block delimiters
  • Shortening of variable and function names
  • Collapsing the number of JavaScript files
If you have an extension in the store with obfuscated code, please review our updated content policies as well as our recommended minification techniques for Google Developers, and submit a new compliant version before January 1st, 2019.

Required 2-step verification
In 2019, enrollment in 2-Step Verification will be required for Chrome Web Store developer accounts. If your extension becomes popular, it can attract attackers who want to steal it by hijacking your account, and 2-Step Verification adds an extra layer of security by requiring a second authentication step from your phone or a physical security key. We strongly recommend that you enroll as soon as possible.
For even stronger account security, consider the Advanced Protection Program. Advanced protection offers the same level of security that Google relies on for its own employees, requiring a physical security key to provide the strongest defense against phishing attacks.

Looking ahead: Manifest v3
In 2019 we will introduce the next extensions manifest version. Manifest v3 will entail additional platform changes that aim to create stronger security, privacy, and performance guarantees. We want to help all developers fall into the pit of success; writing a secure and performant extension in Manifest v3 should be easy, while writing an insecure or non-performant extension should be difficult.
Some key goals of manifest v3 include:
  • More narrowly-scoped and declarative APIs, to decrease the need for overly-broad access and enable more performant implementation by the browser, while preserving important functionality
  • Additional, easier mechanisms for users to control the permissions granted to extensions
  • Modernizing to align with new web capabilities, such as supporting Service Workers as a new type of background process
We intend to make the transition to manifest v3 as smooth as possible and we’re thinking carefully about the rollout plan. We’ll be in touch soon with more specific details.
We recognize that some of the changes announced today may require effort in the future, depending on your extension. But we believe the collective result will be worth that effort for all users, developers, and for the long term health of the Chrome extensions ecosystem. We’re committed to working with you to transition through these changes and are very interested in your feedback. If you have questions or comments, please get in touch with us on the Chromium extensions forum.
Kategorie: Hacking & Security