Implant Teardown

Posted by Ian Beer, Project Zero In the earlier posts we examined how the attackers gained unsandboxed code execution as root on iPhones. At the end of each chain we saw the attackers calling posixspawn, passing the path to their implant binary which they dropped in /tmp. This starts the implant...

A Shadow of our Former Self

Posted by James Forshaw of Google Project Zero “Necessity is the Mother of Invention” as it’s said, and this is no more true than when looking for and exploiting security vulnerabilities. When new exploit mitigations are introduced, either a way of bypassing the mitigation is needed or an...

Adventures in Video Conferencing Part 1: The Wild World of WebRTC

Posted by Natalie Silvanovich, Project Zero Over the past five years, video conferencing support in websites and applications has exploded. Facebook, WhatsApp, FaceTime and Signal are just a few of the many ways that users can make audio and video calls across networks. While a lot of research ha...

The Definitive Guide on Win32 to NT Path Conversion

Posted by James Forshaw, path’ological reverse engineer. How the Win32 APIs process file paths on Windows NT is a tale filled with backwards compatibility hacks, weird behaviour, and beauty†. Incorrect handling of Win32 paths can lead to security vulnerabilities. This blog post is to try and give...

The curious tale of a fake Carrier.app

Posted by Ian Beer, Google Project Zero NOTE: This issue was CVE-2021-30983 was fixed in iOS 15.2 in December 2021. Towards the end of 2021 Google's Threat Analysis Group TAG shared an iPhone app with me: App splash screen showing the Vodafone carrier logo and the text "My Vodafone" not the...

MMS Exploit Part 3: Constructing the Memory Corruption Primitives

Posted by Mateusz Jurczyk, Project Zero This post is the third of a multi-part series capturing my journey from discovering a vulnerable little-known Samsung image codec, to completing a remote zero-click MMS attack that worked on the latest Samsung flagship devices. New posts will be published a...

Over The Air - Vol. 2, Pt. 1: Exploiting The Wi-Fi Stack on Apple Devices

Posted by Gal Beniamini, Project Zero Earlier this year we performed research into Broadcom’s Wi-Fi stack. Due to the ubiquity of Broadcom’s stack, we chose to conduct our prior research through the lens of one affected family of products -- the Android ecosystem. To paint a more complete picture...

One font vulnerability to rule them all #4: Windows 8.1 64-bit sandbox escape exploitation

Posted by Mateusz Jurczyk of Google Project Zero This is the final part 4 of the “One font vulnerability to rule them all” blog post series. In the previous posts, we introduced the “blend” PostScript operator vulnerability and successfully used it to first exploit Adobe Reader, and later escape...

A Tale of Two Exploits

Posted by Natalie Silvanovich, Collision Investigator and Object Field Examiner CVE-2015-0336 is a type confusion vulnerability in the AS2 NetConnection class. I reported this issue in January and soon wrote a proof-of-concept exploit for the bug. The issue was patched by Adobe in March and less...

One Byte to rule them all

Posted by Brandon Azad, Project Zero One Byte to rule them all, One Byte to type them, One Byte to map them all, and in userspace bind them -- Comment above vmmapcopyt For the last several years, nearly all iOS kernel exploits have followed the same high-level flow: memory corruption and fake Mac...

FF Sandbox Escape (CVE-2020-12388)

By James Forshaw, Project Zero In my previous blog post I discussed an issue with the Windows Kernel’s handling of Restricted Tokens which allowed me to escape the Chrome GPU sandbox. Originally I’d planned to use Firefox for the proof-of-concept as Firefox uses the same effective sandbox level a...

Part II: Returning to Adobe Reader symbols on macOS

Posted by Mateusz Jurczyk, Project Zero In a blog post titled "The story of Adobe Reader symbols" published in October 2019, I presented an analysis of the debug symbols shipped with some older versions of Adobe Reader for Unix-family systems released between 1997-2013. Such symbols can prove...

Adventures in Video Conferencing Part 3: The Even Wilder World of WhatsApp

Posted by Natalie Silvanovich, Project Zero WhatsApp is another application that supports video conferencing that does not use WebRTC as its core implementation. Instead, it uses PJSIP, which contains some WebRTC code, but also contains a substantial amount of other code, and predates the WebRTC...

Over The Air: Exploiting Broadcom’s Wi-Fi Stack (Part 2)

Posted by Gal Beniamini, Project Zero In this blog post we'll continue our journey into gaining remote kernel code execution, by means of Wi-Fi communication alone. Having previously developed a remote code execution exploit giving us control over Broadcom’s Wi-Fi SoC, we are now left with the ta...

Notes on Windows Uniscribe Fuzzing

Posted by Mateusz Jurczyk of Google Project Zero Among the total of 119 vulnerabilities with CVEs fixed by Microsoft in the March Patch Tuesday a few weeks ago, there were 29 bugs reported by us in the font-handling code of the Uniscribe library. Admittedly the subject of font-related security ha...

The poisoned NUL byte, 2014 edition

Posted by Chris Evans, Exploit Writer Underling to Tavis Ormandy Back in this 1998 post to the Bugtraq mailing list, Olaf Kirch outlined an attack he called “The poisoned NUL byte”. It was an off-by-one error leading to writing a NUL byte outside the bounds of the current stack frame. On i386...

Windows Bug Class: Accessing Trapped COM Objects with IDispatch

Posted by James Forshaw, Google Project Zero Object orientated remoting technologies such as DCOM and .NET Remoting make it very easy to develop an object-orientated interface to a service which can cross process and security boundaries. This is because they're designed to support a wide range of...

Over The Air - Vol. 2, Pt. 2: Exploiting The Wi-Fi Stack on Apple Devices

Posted by Gal Beniamini, Project Zero In this blog post we’ll continue our journey towards over-the-air exploitation of the iPhone, by means of Wi-Fi communication alone. This part of the research will focus on the firmware running on Broadcom’s Wi-Fi SoC present on the iPhone 7. We’ll begin by...

The Great DOM Fuzz-off of 2017

Posted by Ivan Fratric, Project Zero Introduction Historically, DOM engines have been one of the largest sources of web browser bugs. And while in the recent years the popularity of those kinds of bugs in targeted attacks has somewhat fallen in favor of Flash which allows for cross-browser exploi...

Exploiting .NET Managed DCOM

Posted by James Forshaw, Project Zero One of the more interesting classes of security vulnerabilities are those affecting interoperability technology. This is because these vulnerabilities typically affect any application using the technology, regardless of what the application actually does. Als...

Lifting the (Hyper) Visor: Bypassing Samsung’s Real-Time Kernel Protection

Posted by Gal Beniamini, Project Zero Traditionally, the operating system’s kernel is the last security boundary standing between an attacker and full control over a target system. As such, additional care must be taken in order to ensure the integrity of the kernel. First, when a system boots, t...

Exploiting a Leaked Thread Handle

Posted by logged on user, James Forshaw. Once in awhile you’ll find a bug that allows you to leak a handle opened in a privileged process into a lower privileged process. I found just such a bug in the Secondary Logon service on Windows, which was fixed this month as MS16-032. The bug allowed you...

RC4 Is Still Considered Harmful

By James Forshaw, Project Zero I've been spending a lot of time researching Windows authentication implementations, specifically Kerberos. In June 2022 I found an interesting issue number 2310 with the handling of RC4 encryption that allowed you to authenticate as another user if you could either...

Mitigations are attack surface, too

Posted by Jann Horn, Project Zero Introduction This blog post discusses a bug leading to memory corruption in Samsung's Android kernel specifically the kernel of the Galaxy A50, A505FN - I haven't looked at Samsung's kernels for other devices. I will describe the bug and how I wrote a very...

The Problems and Promise of WebAssembly

Posted by Natalie Silvanovich, Project Zero WebAssembly is a format that allows code written in assembly-like instructions to be run from JavaScript. It has recently been implemented in all four major browsers. We reviewed each browser’s WebAssembly implementation and found three vulnerabilities...

A 0-click exploit chain for the Pixel 10: When a Door Closes, a Window Opens

Posted by Seth Jenkins We recently published an exploit chain for the Google Pixel 9 that demonstrated it was possible to go from a zero-click context to root on Android in just two exploits. The Dolby 0-click vulnerability existed across all of Android, until it was patched in January 2026. Whil...

Windows Tooling Updates: OleView.NET

Posted by James Forshaw, Google Project Zero This is a short blog post about some recent improvements I've been making to the OleView.NET tool which has been released as part of version 1.16. The tool is designed to discover the attack surface of Windows COM and find security vulnerabilities such...

The State of State Machines

Posted by Natalie Silvanovich, Project Zero On January 29, 2019, a serious vulnerability was discovered in Group FaceTime which allowed an attacker to call a target and force the call to connect without user interaction from the target, allowing the attacker to listen to the target’s surroundings...

Down the Rabbit-Hole...

Posted by Tavis Ormandy, Security Research Over-Engineer. “Sometimes, hacking is just someone spending more time on something than anyone else might reasonably expect.”1 I often find it valuable to write simple test cases confirming things work the way I think they do. Sometimes I can’t explain t...

voucher_swap: Exploiting MIG reference counting in iOS 12

Posted by Brandon Azad, Project Zero In this post I'll describe how I discovered and exploited CVE-2019-6225, a MIG reference counting vulnerability in XNU's taskswapmachvoucher function. We'll see how to exploit this bug on iOS 12.1.2 to build a fake kernel task port, giving us the ability to re...

Stagefrightened?

Posted by Mark Brand, Bypasser of Mitigations There’s been a lot of attention recently around a number of vulnerabilities in Android’s libstagefright. There’s been a lot of confusion about the remote exploitability of the issues, especially on modern devices. In this blog post we will demonstrate...

A Token’s Tale

Posted by James Forshaw currently impersonating NT AUTHORITY\SYSTEM. Much as I enjoy the process of vulnerability research sometimes there’s a significant disparity between the difficulty of finding a vulnerability and exploiting it. The Project Zero blog contains numerous examples of complex...

More Mac OS X and iPhone sandbox escapes and kernel bugs

Posted by Ian Beer A couple of weeks ago Apple released OS X 10.9.5 and iOS 8 which fixed a number of sandbox escapes and privilege escalation bugs found by Project Zero. All-bar-one of these bugs were found via manual source code auditing where there was source and binary analysis where there...

What does a pointer look like, anyway?

Posted by Chris Evans, Renderer of Modern Art In Adobe’s August 2014 Flash Player security update, we see: These updates resolve memory leakage vulnerabilities that could be used to bypass memory address randomization CVE-2014-0540, CVE-2014-0542, CVE-2014-0543, CVE-2014-0544, CVE-2014-0545. I...

Windows Kernel Logic Bug Class: Access Mode Mismatch in IO Manager

Posted by James Forshaw, Project Zero This blog post is an in-depth look at an interesting logic bug class in the Windows Kernel and what I did to try to get it fixed with our partners at Microsoft. The maximum impact of the bug class is local privilege escalation if kernel and driver developers...

Injecting Code into Windows Protected Processes using COM - Part 2

Posted by James Forshaw, Project Zero In my previous blog I discussed a technique which combined numerous issues I’ve previously reported to Microsoft to inject arbitrary code into a PPL-WindowsTCB process. The techniques presented don’t work for exploiting the older, stronger Protected Processes...

Life After the Isolated Heap

Posted by Natalie Silvanovich, Mourner of Lost Exploits Over the past few months, Adobe has introduced a number of changes to the Flash Player heap with the goal of reducing the exploitability of certain types of vulnerabilities in Flash, especially use-after-frees. I wrote an exploit involving t...

Race you to the kernel!

Posted by Ian Beer of Google Project Zero The OS X and iOS kernel code responsible for loading a setuid root binary invalidates the old task port after first swapping the new virtual memory map pointer into the old task object, leaving a short race window where you can manipulate the memory of an...

Taming the wild copy: Parallel Thread Corruption

Posted by Chris Evans, Winner of the occasional race Back in 2002, a very interesting vulnerability was found and fixed in the Apache web server. Relating to a bug in chunked encoding handing, the vulnerability caused a memcpy call with a negative length with the destination on the stack. Of...

(^Exploiting)\s*(CVE-2015-0318)\s*(in)\s*(Flash$)

Posted by Mark Brand, Irregular Expressionist So; issue 199/PSIRT-3161/CVE-2015-0318. Quick summary - it’s a bug in the PCRE regex engine as used in Flash. Note that the published version of the avmplus code is significantly out of date; there are a number of other vulnerabilities present that ha...

Exploiting Android Messengers with WebRTC: Part 1

Posted by Natalie Silvanovich, Project Zero This is a three-part series on exploiting messenger applications using vulnerabilities in WebRTC. This series highlights what can go wrong when applications don't apply WebRTC patches and when the communication and notification of security issues breaks...

How to unc0ver a 0-day in 4 hours or less

By Brandon Azad, Project Zero At 3 PM PDT on May 23, 2020, the unc0ver jailbreak was released for iOS 13.5 the latest signed version at the time of release using a zero-day vulnerability and heavy obfuscation. By 7 PM, I had identified the vulnerability and informed Apple. By 1 AM, I had sent App...

The Windows Registry Adventure #6: Kernel-mode objects

Posted by Mateusz Jurczyk, Google Project Zero Welcome back to the Windows Registry Adventure! In the previous installment of the series, we took a deep look into the internals of the regf hive format. Understanding this foundational aspect of the registry is crucial, as it illuminates the design...

Windows‌ ‌Exploitation‌ ‌Tricks:‌ ‌Spoofing‌ ‌Named‌ ‌Pipe‌ ‌Client‌ ‌PID‌

Posted by James Forshaw, Project Zero While researching the Access Mode Mismatch in IO Manager bug class I came across an interesting feature in named pipes which allows a server to query the connected clients PID. This feature was introduced in Vista and is exposed to servers through the...

What is a "good" memory corruption vulnerability?

Posted by Chris Evans, register whisperer. Part 1 of 4. There are a lot of memory corruption vulnerabilities in software, but not all are created equal. To a certain degree, the “usefulness” of a given memory corruption vulnerability is determined by how reliably it might be exploited. In some...

Feedback and data-driven updates to Google’s disclosure policy

Posted by Chris Evans and Ben Hawkes, Project Zero; Heather Adkins, Matt Moore and Michal Zalewski, Google Security; Gerhard Eschelbeck, Vice President, Google Security Disclosure deadlines have long been an industry standard practice. They improve end-user security by getting security patches to...

MMS Exploit Part 4: MMS Primer, Completing the ASLR Oracle

Posted by Mateusz Jurczyk, Project Zero This post is the fourth of a multi-part series capturing my journey from discovering a vulnerable little-known Samsung image codec, to completing a remote zero-click MMS attack that worked on the latest Samsung flagship devices. New posts will be published ...

The Qualcomm DSP Driver - Unexpectedly Excavating an Exploit

Posted by Seth Jenkins, Google Project Zero This blog post provides a technical analysis of exploit artifacts provided to us by Google's Threat Analysis Group TAG from Amnesty International. Amnesty’s report on these exploits is available here. Thanks to both Amnesty International and Google's...

The core of Apple is PPL: Breaking the XNU kernel's kernel

Posted by Brandon Azad, Project Zero While doing research for the one-byte exploit technique, I considered several ways it might be possible to bypass Apple's Page Protection Layer PPL using just a physical address mapping primitive, that is, before obtaining kernel read/write or defeating PAC...

Owning Internet Printing - A Case Study in Modern Software Exploitation

Guest posted by Neel Mehta [email protected] - June 19th, 2015 Abstract Modern exploit mitigations draw attackers into a game of diminishing marginal returns. With each additional mitigation added, a subset of software bugs become unexploitable, and others become difficult to exploit, requiring...