We released our Fuzzilli-based V8 Sandbox fuzzer: github.com/googleprojec... It explores the heap to find interesting objects and corrupts them in a deterministic way using V8's memory corruption API. Happy fuzzing!

I have often stated that well-implemented memory tagging will be a game changer for memory corruptions. And it seems that with the next iPhone it's finally here: security.apple.com/blog/memory-...

We derestricted crbug.com/382005099 today which might just be my favorite bug of the last few years: bad interaction between WebAudio changing the CPU's handling of floats and V8 not expecting that. See crbug.com/382005099#co... for a PoC exploit. Also affected other browsers

More details: docs.google.com/document/d/1... Implementation: source.chromium.org/chromium/chr...

We derestricted a number of vulnerabilities found by Big Sleep in JavaScriptCore today: issuetracker.google.com/issues?q=com... All of them were fixed in the iOS 26.1 (and equivalent) update last month. Definitely some cool bugs in there!

I've uploaded the slides of my recent talk "JS Engine Security in 2025": saelo.github.io/presentation.... I think there'll also be a recording available at some point (otherwise I can make one as not everything's in the slides). Fantastic conference as usual, big thanks to the PoC Crew!

Some more cool JS Engine bugs found by Big Sleep were fixed in yesterday's Apple security updates: support.apple.com/en-us/125632 Technical details will be available soon at issuetracker.google.com/issues?q=com...

We are going to hold VXCON www.vxcon.hk

This time is a real thrilling announcement as our paper about template-based fuzzing for JavaScript engine is accepted in OOPSLA24-25. Thank you so much to every co-authors including Ken Wong, Dongwei Xiao, Dr. Daoyuan Wu Dr. Shuai Wang and Yiteng Peng. What a good evening!

Congratulations to Carl Smith from v8 Security team and join Blackhat USA review board as guest reviewer. He is willing to share, open-minded, and a hardcore researcher and developer. @rwx.page

The countries always attempt to hack into vendor platforms or apps, my idea is making a “Realistic Honeypot Platform” and let them in, capture as much as information about them and … cloud.google.com/blog/topics/...

Our first Chrome VRP bounty, it is an inspiration and keep going.

We got our first Google Chrome bounty for minimum wage or McDonalds before Christmas 🎄. Getting money from Google is mission impossible.

We are glad to complete VXCON. Thank you so much to every speakers, guest, and crew member to make it happen. #vxcon #vxrl

Here's another V8 sandbox design document, this time discussing how sensitive ("trusted") V8-internal objects (such as BytecodeArrays) can be protected: docs.google.com/document/d/1... This should be one of the last pieces of infrastructure required for the sandbox.

Finally got around to publishing the slides of my talk @offensivecon.bsky.social from ~two weeks ago. Sorry for the delay! The V8 Heap Sandbox: saelo.github.io/presentation... Fantastic conference, as usual! :)

Another big step towards becoming a security boundary: today we’re expanding the VRP for the V8 Sandbox * No longer limited to d8 * Rewards for controlled writes increased to $20k * Any memory corruption outside the sandbox is now in scope bughunters.google.com/about/rules/... Happy hacking!

VXCON finished and thank you so much to everyone.