Anthropic's Frontier Red Team said in a research post on October 27 that an unreleased internal Claude model found vulnerabilities across Chrome, Safari, Android, Windows and Linux and chained them into five working proof-of-concept exploits in lab tests. Anthropic says every flaw was reported to the affected vendor first and has been patched, and there is no evidence of real-world exploitation.

The Chrome chain combined four bugs to escape the browser sandbox and run code on a Mac within seconds of a page loading; Anthropic says its reports to Google produced 62 high or critical CVEs, including 13 sandbox escapes, fixed in Chrome 156. The other chains included a zero-click Linux exploit reaching root in 53 minutes (CVE-2026-98432, CVSS 9.8), a Safari same-origin break, a locked Pixel 9 bypass over USB, and a Windows crash bug (CVE-2026-33096).

Anthropic has not named the model or said whether it will be released, and it characterizes the work as needing little human involvement beyond an initial prompt. Vendor records credit Anthropic researchers assisted by Claude for some of the fixes, but do not independently account for all 62 Chrome CVEs.