XBOW: AI agents built a Chrome full-chain exploit in six days
Four XBOW researchers directed AI agents running a public OpenAI model to build a working Chrome exploit chain in six days.
· XBOW · Research by Oege de Moor, Brendan Dolan-Gavitt, Andres Luksenberg, Baul Lee, Willem Pinckaers
XBOW reports that four of its researchers directed AI agents running OpenAI's publicly available GPT-5.6 Sol to build a three-stage Chrome exploit chain in six days, and that Google paid its top $250,000 full-chain reward.
01What happened
XBOW published the result on October 13, 2026, after Google awarded it the top $250,000 Chrome reward for a full exploit chain. Oege de Moor writes that Brendan Dolan-Gavitt, Andres Luksenberg, Baul Lee and Willem Pinckaers rebuilt the chain between August 2 and August 7, 2026, in Las Vegas during Black Hat and DEF CON. An earlier attempt was disqualified because Google already knew one of its bugs.
02How it works
The chain is three independent stages, each with a spare bug, so the team could swap a stage out when Google said a flaw was already known. AI agents running GPT-5.6 Sol and earlier OpenAI models searched Chrome's source code, tested ideas, built proofs of concept and wrote the first exploit drafts. The four humans set the strategy, chose where to look, checked the agents' work and redirected them on the results. XBOW does not publish the bug details or any CVE ids in this post.
03Who is affected
Chrome users on Windows were the target. XBOW's post is titled around a chain affecting a billion users, and describes an attacker using Chrome to take over a Windows machine remotely. XBOW states that all three bugs are fixed and that the exploit was never used against Chrome users.
04What to do
Update Chrome and relaunch the browser, which is XBOW's own advice to readers: a staged update only takes effect after a restart.
Sources 2 links, all fetched
- 1xbow.comXBOW Write-Up
- 2chromium.googlesource.comChrome VRP FAQ