This shouldn't have happened: A vulnerability postmortem

Posted by Tavis Ormandy, Project Zero Introduction This is an unusual blog post. I normally write posts to highlight some hidden attack surface or interesting complex vulnerability class. This time, I want to talk about a vulnerability that is neither of those things. The striking thing about thi...

Bypassing VirtualBox Process Hardening on Windows

Posted by James Forshaw, Project Zero Processes on Windows are securable objects, which prevents one user logged into a Windows machine from compromising another user’s processes. This is a pretty important security feature, at least from the perspective of a non-administrator user. The security...

JITSploitation III: Subverting Control Flow

Posted by Samuel Groß, Project Zero This three-part series highlights the technical challenges involved in finding and exploiting JavaScript engine vulnerabilities in modern web browsers and evaluates current exploit mitigation technologies. The exploited vulnerability, CVE-2020-9802, was fixed i...

Using Binary Diffing to Discover Windows Kernel Memory Disclosure Bugs

Posted by Mateusz Jurczyk of Google Project Zero Patch diffing is a common technique of comparing two binary builds of the same code – a known-vulnerable one and one containing a security fix. It is often used to determine the technical details behind ambiguously-worded bulletins, and to establis...

The Windows Registry Adventure #7: Attack surface analysis

Posted by Mateusz Jurczyk, Google Project Zero In the first three blog posts of this series, I sought to outline what the Windows Registry actually is, its role, history, and where to find further information about it. In the subsequent three posts, my goal was to describe in detail how this...

An Autopsy on a Zombie In-the-Wild 0-day

Posted by Maddie Stone, Google Project Zero Whenever there’s a new in-the-wild 0-day disclosed, I’m very interested in understanding the root cause of the bug. This allows us to then understand if it was fully fixed, look for variants, and brainstorm new mitigations. This blog is the story of a...

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...

An analysis of an in-the-wild iOS Safari WebContent to GPU Process exploit

By Ian Beer A graph representation of the sandbox escape NSExpression payload In April this year Google's Threat Analysis Group, in collaboration with Amnesty International, discovered an in-the-wild iPhone zero-day exploit chain being used in targeted attacks delivered via malicious link. The...

JITSploitation I: A JIT Bug

By Samuel Groß, Project Zero This three-part series highlights the technical challenges involved in finding and exploiting JavaScript engine vulnerabilities in modern web browsers and evaluates current exploit mitigation technologies. The exploited vulnerability, CVE-2020-9802, was fixed in iOS...

The quantum state of Linux kernel garbage collection CVE-2021-0920 (Part I)

A deep dive into an in-the-wild Android exploit Guest Post by Xingyu Jin, Android Security Research This is part one of a two-part guest blog post, where first we'll look at the root cause of the CVE-2021-0920 vulnerability. In the second post, we'll dive into the in-the-wild 0-day exploitation o...

SockPuppet: A Walkthrough of a Kernel Exploit for iOS 12.4

Posted by Ned Williamson, 20% on Project Zero Introduction I have a somewhat unique opportunity in this writeup to highlight my experience as an iOS research newcomer. Many high quality iOS kernel exploitation writeups have been published, but those often feature weaker initial primitives combine...

Enabling QR codes in Internet Explorer, or a story of a cross-platform memory disclosure

Posted by Mateusz Jurczyk of Google Project Zero In the previous series of posts parts 1 2 3 4, we discussed the exploitation process of a serious “blend” vulnerability CVE-2015-0093 / CVE-2015-3052, which was special in that it provided the attacker with an extremely powerful primitive arbitrary...

Understanding Network Access in Windows AppContainers

Posted by James Forshaw, Project Zero Recently I've been delving into the inner workings of the Windows Firewall. This is interesting to me as it's used to enforce various restrictions such as whether AppContainer sandboxed applications can access the network. Being able to bypass network...

A Look at iMessage in iOS 14

Posted By Samuel Groß, Project Zero On December 20, Citizenlab published “The Great iPwn”, detailing how “Journalists were Hacked with Suspected NSO Group iMessage ‘Zero-Click’ Exploit”. Of particular interest is the following note: “We do not believe that the exploit works against iOS 14 and...

Remote iPhone Exploitation Part 2: Bringing Light into the Darkness -- a Remote ASLR Bypass

Posted by Samuel Groß, Project Zero This post is the second in a series about a remote, interactionless iPhone exploit over iMessage.The first blog post, which introduced the exploited vulnerability, can be found here. The initial primitive gained from the vulnerability is an absolute address...

The Windows Registry Adventure #8: Practical exploitation of hive memory corruption

Posted by Mateusz Jurczyk, Google Project Zero In the previous blog post, we focused on the general security analysis of the registry and how to effectively approach finding vulnerabilities in it. Here, we will direct our attention to the exploitation of hive-based memory corruption bugs, i.e.,...

Mind the Gap

By Ian Beer, Project Zero Note: The vulnerabilities discussed in this blog post CVE-2022-33917 are fixed by the upstream vendor, but at the time of publication, these fixes have not yet made it downstream to affected Android devices including Pixel, Samsung, Xiaomi, Oppo and others. Devices with ...

CVE-2021-1782, an iOS in-the-wild vulnerability in vouchers

Posted by Ian Beer, Google Project Zero This blog post is my analysis of a vulnerability exploited in the wild and patched in early 2021. Like the writeup published last week looking at an ASN.1 parser bug, this blog post is based on the notes I took as I was analyzing the patch and trying to...

Exploiting the DRAM rowhammer bug to gain kernel privileges

Rowhammer blog post draft Posted by Mark Seaborn, sandbox builder and breaker, with contributions by Thomas Dullien, reverse engineer This guest post continues Project Zero’s practice of promoting excellence in security research on the Project Zero blog Overview “Rowhammer” is a problem with some...

Windows 10^H^H Symbolic Link Mitigations

Posted by James Forshaw, abusing symbolic links like it’s 1999. For the past couple of years I’ve been researching Windows elevation of privilege attacks. This might be escaping sandboxing or gaining system privileges. One of the techniques I’ve used multiple times is abusing the symbolic link...

FORCEDENTRY: Sandbox Escape

Posted by Ian Beer & Samuel Groß of Google Project Zero We want to thank Citizen Lab for sharing a sample of the FORCEDENTRY exploit with us, and Apple’s Security Engineering and Architecture SEAR group for collaborating with us on the technical analysis. Any editorial opinions reflected below ar...

Zooming in on Zero-click Exploits

Posted by Natalie Silvanovich, Project Zero Zoom is a video conferencing platform that has gained popularity throughout the pandemic. Unlike other video conferencing systems that I have investigated, where one user initiates a call that other users must immediately accept or reject, Zoom calls ar...

Attacking the Qualcomm Adreno GPU

Posted by Ben Hawkes, Project Zero When writing an Android exploit, breaking out of the application sandbox is often a key step. There are a wide range of remote attacks that give you code execution with the privileges of an application like the browser or a messaging application, but a sandbox...

Driving forward in Android drivers

Posted by Seth Jenkins, Google Project Zero Introduction Android's open-source ecosystem has led to an incredible diversity of manufacturers and vendors developing software that runs on a broad variety of hardware. This hardware requires supporting drivers, meaning that many different codebases...

A survey of recent iOS kernel exploits

Posted by Brandon Azad, Project Zero I recently found myself wishing for a single online reference providing a brief summary of the high-level exploit flow of every public iOS kernel exploit in recent years; since no such document existed, I decided to create it here. This post summarizes origina...

Fuzzing ImageIO

Posted by Samuel Groß, Project Zero This blog post discusses an old type of issue, vulnerabilities in image format parsers, in a newer context: on interactionless code paths in popular messenger apps. This research was focused on the Apple ecosystem and the image parsing API provided by it: the...

Virtually Unlimited Memory: Escaping the Chrome Sandbox

Posted by Mark Brand, Exploit Technique Archaeologist. Introduction After discovering a collection of possible sandbox escape vulnerabilities in Chrome, it seemed worthwhile to exploit one of these issues as a full-chain exploit together with a renderer vulnerability to get a better understanding...

MMS Exploit Part 1: Introduction to the Samsung Qmage Codec and Remote Attack Surface

Posted by Mateusz Jurczyk, Project Zero This post is the first 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...

pwn4fun Spring 2014 - Safari - Part II

Posted by Ian Beer TL;DR An OS X GPU driver trusted a user-supplied kernel C++ object pointer and called a virtual function. The IOKit registry contained kernel pointers which were used defeat kASLR. A kernel ROP payload ran Calculator.app as root using a convenient kernel API. Overview of part I...

A Very Powerful Clipboard: Analysis of a Samsung in-the-wild exploit chain

Posted by Maddie Stone, Project Zero Note: The three vulnerabilities discussed in this blog were all fixed in Samsung’s March 2021 release. They were fixed as CVE-2021-25337, CVE-2021-25369, CVE-2021-25370. To ensure your Samsung device is up-to-date under settings you can check that your device ...

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...

Remote iPhone Exploitation Part 1: Poking Memory via iMessage and CVE-2019-8641

Posted by Samuel Groß, Project Zero Introduction This is the first blog post in a three-part series that will detail how a vulnerability in iMessage can be exploited remotely without any user interaction on iOS 12.4 fixed in iOS 12.4.1 in August 2019. It is essentially a more detailed version of ...

You Won't Believe what this One Line Change Did to the Chrome Sandbox

Posted by James Forshaw, Project Zero The Chromium sandbox on Windows has stood the test of time. It’s considered one of the better sandboxing mechanisms deployed at scale without requiring elevated privileges to function. For all the good, it does have its weaknesses. The main one being the...

Attacking ECMAScript Engines with Redefinition

Posted by Natalie Silvanovich = function return n; ECMAScript has a property where almost all functions and variables can be dynamically redefined. This can lead to vulnerabilities in situations where native code assumes a function or variable behaves a certain way when accessed or does not have...

In-the-wild iOS Exploit Chain 4

Posted by Ian Beer, Project Zero TL;DR This exploit chain supported iOS 12-12.1, although the two vulnerabilities were unpatched when we discovered the chain in the wild. It was these two vulnerabilities which we reported to Apple with a 7-day deadline, leading to the release of iOS 12.1.4. The...

Taking a page from the kernel's book: A TLB issue in mremap()

Posted by Jann Horn, Project Zero This is a technical blog post about TLB flushing bugs in kernels, intended for people interested in kernel security and memory management. Introduction: Bugs in Memory Management code There have been some pretty scary bugs in memory management in the past, like:...

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...

A year of Windows kernel font fuzzing #1: the results

Posted by Mateusz Jurczyk of Google Project Zero This post series is about how we used at-scale fuzzing to discover and report a total of 16 vulnerabilities in the handling of TrueType and OpenType fonts in the Windows kernel during the last year. In part 1 here, we present a general overview of...

Over The Air: Exploiting Broadcom’s Wi-Fi Stack (Part 1)

Posted by Gal Beniamini, Project Zero It’s a well understood fact that platform security is an integral part of the security of complex systems. For mobile devices, this statement rings even truer; modern mobile platforms include multiple processing units, all elaborately communicating with one...

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 Windows Registry Adventure #3: Learning resources

Posted by Mateusz Jurczyk, Google Project Zero When tackling a new vulnerability research target, especially a closed-source one, I prioritize gathering as much information about it as possible. This gets especially interesting when it's a subsystem as old and fundamental as the Windows registry...

Exploiting CVE-2022-42703 - Bringing back the stack attack

Seth Jenkins, Project Zero This blog post details an exploit for CVE-2022-42703 P0 issue 2351 - Fixed 5 September 2022, a bug Jann Horn found in the Linux kernel's memory management MM subsystem that leads to a use-after-free on struct anonvma. As the bug is very complex I certainly struggle to...

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...

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...

DER Entitlements: The (Brief) Return of the Psychic Paper

Posted by Ivan Fratric, Project Zero Note: The vulnerability discussed here, CVE-2022-42855, was fixed in iOS 15.7.2 and macOS Monterey 12.6.2. While the vulnerability did not appear to be exploitable on iOS 16 and macOS Ventura, iOS 16.2 and macOS Ventura 13.1 nevertheless shipped hardening...

Adventures in Video Conferencing Part 2: Fun with FaceTime

Posted by Natalie Silvanovich, Project Zero FaceTime is Apple’s video conferencing application for iOS and Mac. It is closed source, and does not appear to use any third-party libraries for its core functionality. I wondered whether fuzzing the contents of FaceTime’s audio and video streams would...

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...

Deja-XNU

Posted by Ian Beer, Google Project Zero This blog post revisits an old bug found by Pangu Team and combines it with a new, albeit very similar issue I recently found to try to build a "perfect" exploit for iOS 7.1.2. State of the art An idea I've wanted to play with for a while is to revisit old...

Windows Exploitation Tricks: Exploiting Arbitrary Object Directory Creation for Local Elevation of Privilege

Posted by James Forshaw, Project Zero And we’re back again for another blog in my series on Windows Exploitation tricks. This time I’ll detail how I was able to exploit Issue 1550 which results in an arbitrary object directory being created by using a useful behavior of the CSRSS privileged...

Pandavirtualization: Exploiting the Xen hypervisor

Posted by Jann Horn, Project Zero On 2017-03-14, I reported a bug to Xen's security team that permits an attacker with control over the kernel of a paravirtualized x86-64 Xen guest to break out of the hypervisor and gain full control over the machine's physical memory. The Xen Project publicly...