Security startup XBOW discloses on October 13 building a Chrome full-chain exploit in 6 days for $40K in tokens using GPT-5.6 Sol, earning Google's $250K bounty
XBOW disclosed on October 13 that during Black Hat and DEF CON its team built a Chrome full-chain exploit using OpenAI's GPT-5.6 Sol and about $40K in tokens, chaining three zero-days in V8 Maglev, the animated WebP decoder and Crashpad, affecting about 1 billion Windows users; Google paid the top $250K bounty.
Security research startup XBOW disclosed on October 13 that during Black Hat and DEF CON its team used OpenAI's publicly available GPT-5.6 Sol model and about $40,000 in token charges to build a full Chrome exploit that escapes the browser's sandbox on Windows and affects about 1 billion users, in just six days. The chain combined a V8 mid-tier Maglev compiler issue, an animated WebP decoder sandbox escape (CVE-2026-85045) and a memory-safety bug in Crashpad. Google confirmed all three flaws and paid XBOW the top $250,000 bounty, with fixes shipped in Chrome 152.0.7977.65 on August 25 and 152.0.7977.82 on September 3; XBOW said this is the first $250,000 full-chain reward under Google's 2026 Chrome Vulnerability Reward Program rules. XBOW founder Oege de Moor cited a three-letter intelligence agency veteran saying such chains used to take a six-month specialist team; team member Brendan Dolan-Gavitt said LLMs have significantly lowered the bar for attackers, while XBOW researchers still selected targets, split tasks, challenged AI results and chose which components to chain.