CVE-2026-87491: Chrome V8 Zero-Day Exploited in the Wild Enables Arbitrary Code Execution

Google Chrome CVE-2026-87491 is an actively exploited out-of-bounds write vulnerability in the V8 JavaScript/WebAssembly engine affecting Chrome versions prior to 153.0.8010.36; Google released a patch in Chrome 153 (Sept 8, 2026) and confirmed in-the-wild exploitation while withholding technical details and IOCs. The advisory recommends immediate patching and browser restarts, fleet-wide version verification, and investigation of browser telemetry and endpoint behaviors for potential post-exploitation activity.