Company engineering blog
Original vulnerability research, fuzzing and software security.
4 posts in the last 90 days · newest 27 Oct
10 of 10 posts on this page
Samuel Groß
Summary Project Zero compared two automated tools used by Google to find vulnerabilities in Chrome’s JavaScript engine, V8, on a regular basis. Fuzzilli is a generative JavaScript engine fuzzer and BigSleep is an LLM-based bug finding system. In the past six months, BigSleep…
Natalie Silvanovich
Project Zero often works with software vendors to remediate the vulnerabilities we report and provide broader guidance on making software more secure. Some vendors express concern about potential scenarios in which they are unable to fix vulnerabilities that are causing…
James Forshaw
This short blog post is about abusing a privilege escalation bug that Microsoft recently fixed in Windows, CVE-2026-66804, that I and 14 others reported. This issue is an incomplete fix for CVE-2026-50343, a bug dubbed “Dark Elevator” by Calif. The root cause of the bug was a…
Jann Horn
Many security bugs are race conditions, where multi-threaded execution has to occur with the right interleaving for a negative effect to appear. This creates challenges for several use cases: Confirming bug candidates that have been discovered manually or through static…
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. While we…
Ivan Fratric
Mutational grammar fuzzing is a fuzzing technique in which the fuzzer uses a predefined grammar that describes the structure of the samples. When a sample gets mutated, the mutations happen in such a way that any resulting samples still adhere to the grammar rules, thus the…
James Forshaw
In my previous blog post I mentioned the GetProcessHandleFromHwnd API. This was an API I didn’t know existed until I found a publicly disclosed UAC bypass using the Quick Assist UI Access application. This API looked interesting so I thought I should take a closer look. I…
James Forshaw
In my last blog post I introduced the new Windows feature, Administrator Protection and how it aimed to create a secure boundary for UAC where one didn’t exist. I described one of the ways I was able to bypass the feature before it was released. In total I found 9 bypasses…
Google Project Zero
In the first part of this series, I detailed my journey into macOS security research, which led to the discovery of a type confusion vulnerability (CVE-2024-54529) and a double-free vulnerability (CVE-2025-31235) in the coreaudiod system daemon through a process I call…
James Forshaw
A headline feature introduced in the latest release of Windows 11, 25H2 is Administrator Protection. The goal of this feature is to replace User Account Control (UAC) with a more robust and importantly, securable system to allow a local user to access administrator privileges…