{"id":"EM-20261103-4X0W","url":"https://cyber.eventmonitor.net/incident/EM-20261103-4X0W/","type":"cve","title":"Critical Google Chrome Vulnerability (CVE-2026-121257)","subtitle":"CVE-2026-121257","subject":"CVE-2026-121257","status":"Developing","severity":"critical","affected":[],"headline":null,"born":"2026-11-03T21:17:36.603Z","firstSignal":"2026-11-03T20:42:49.000Z","lastSignal":"2026-11-03T21:17:36.603Z","updated":"2026-11-05T01:06:50.406Z","revision":1,"life":[{"status":"Born","at":"2026-11-03T21:17:36.603Z","why":"second independent source: C6 NVD CVE API 2.0"},{"status":"Developing","at":"2026-11-03T21:17:36.603Z","why":"signals keep joining"}],"changeLog":[{"at":"2026-11-03T20:42:49.000Z","what":"First signal: C41 Red Hat Security Data"},{"at":"2026-11-03T21:17:36.603Z","what":"Born: second source, C6 NVD CVE API 2.0. Page EM-20261103-4X0W created."},{"at":"2026-11-03T21:17:36.603Z","what":"Severity raised to Critical by C6"}],"stages":[{"name":"Disclosed","at":"2026-11-03T21:17:36.603Z","detail":"C6 NVD published"},{"name":"Scored","at":"2026-11-03T21:17:36.603Z","detail":"CVSS 9.6 · EPSS 0.2%"},{"name":"Exploited","at":null,"detail":"No exploitation reported"},{"name":"Advisories","at":null,"detail":"None yet"},{"name":"Vendor Response","at":"2026-11-03T20:42:49.000Z","detail":"C41 published"},{"name":"Resolved","at":null,"detail":"After 14 quiet days"}],"signals":[{"at":"2026-11-03T20:42:49.000Z","source":"C41","sourceName":"Red Hat Security Data","role":"Vendor","severity":2,"title":"Red Hat: CVE-2026-121257 (moderate)","text":"chromium-browser: Use after free in TabStrip","url":"https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-121257.json"},{"at":"2026-11-03T21:17:36.603Z","source":"C6","sourceName":"NVD CVE API 2.0","role":"Database","severity":4,"title":"CVE-2026-121257 (CVSS 9.6)","text":"Use after free in TabStrip in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to potentially execute arbitrary code outside the sandbox via a crafted Chrome extension. (Chromium security severity: Medium)","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121257"}],"crowd":[],"reference":{"nvd":{"published":"2026-11-03T21:17:36.603","score":9.6,"severity":"CRITICAL","desc":"Use after free in TabStrip in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to potentially execute arbitrary code outside the sandbox via a crafted Chrome extension. (Chromium security severity: Medium)","product":"","seen":1793833552675},"kev":null,"epss":{"epss":0.00211,"pct":0.11371,"at":1793825379808},"p0":false},"mergedInto":null,"publisher":"Event Monitor Cyber"}