{"id":"CVE-2026-121221","kind":"vulnerability","aliases":["CVE-2026-121221"],"related":[],"title":"Chrome: V8 type confusion lets a crafted web page run code","description":"Type confusion in V8 in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)","summary":"A type confusion bug in the V8 JavaScript engine of Google Chrome lets a remote attacker run arbitrary code inside the browser sandbox when the victim opens a crafted HTML page. Chromium rates it High severity.","severity":"high","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","runtime","v8"],"not_affected_if":["chrome-updated"],"how_to_check":"- Open Chrome and check the version under Settings > About Chrome, or run `google-chrome --version` on Linux\n- Compare the installed version against `157.0.8103.38`","fix":"- Google Chrome: move to `157.0.8103.38` or later","status":"open","published_at":"2026-11-03T21:17:31+00:00","first_seen_at":"2026-11-03T21:19:27+00:00","triaged_at":"2026-11-03T21:21:29+00:00","updated_at":"2026-11-03T21:21:29+00:00","category":"runtime","confidence":0.8,"triage":{"at":"2026-11-03T21:21:29Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later","reach":"internet","title":"Chrome: V8 type confusion lets a crafted web page run code","impact":"high","summary":"A type confusion bug in the V8 JavaScript engine of Google Chrome lets a remote attacker run arbitrary code inside the browser sandbox when the victim opens a crafted HTML page. Chromium rates it High severity.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","v8"],"confidence":0.8,"fix_status":"available","needs_auth":"no","worst_case":"Attacker runs code inside the browser sandbox on the victim's machine.","analyst_note":"","how_to_check":"- Open Chrome and check the version under Settings > About Chrome, or run `google-chrome --version` on Linux\n- Compare the installed version against `157.0.8103.38`","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: open the menu, go to Help > About Google Chrome, and let it update.","needs_analyst":false,"not_affected_if":["chrome-updated"],"who_is_affected":"Any installed Google Chrome before 157.0.8103.38 is exposed, because the flaw is triggered just by loading a crafted page. Exploitation requires no account and no special setting. Teams that manage browsers for staff should check managed fleets, and browsers on shared kiosks or build agents count too.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000682,"input_tokens":4103,"output_tokens":544,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121221':14A,17A '-2026':13A,16A '157.0.8103.38':67C 'allow':68C 'arbitrari':39B,75C 'attack':37B,71C 'browser':18B,43B 'bug':25B 'chrome':1A,19B,33B,64C 'chromium':53B,85C 'code':11A,40B,76C 'confus':4A,24B,59C 'craft':7A,50B,82C 'cve':12A,15A 'engin':30B 'execut':74C 'googl':32B,63C 'high':56B,88C 'html':51B,83C 'insid':41B,77C 'javascript':29B 'let':5A,34B 'open':48B 'page':9A,52B,84C 'potenti':73C 'prior':65C 'rate':54B 'remot':36B,70C 'run':10A,38B 'runtim':20B 'sandbox':44B,79C 'secur':86C 'sever':57B,87C 'type':3A,23B,58C 'v8':2A,21B,28B,61C 'via':80C 'victim':47B 'web':8A","nicknames":[],"mitigations":[],"who_affected":"Any installed Google Chrome before 157.0.8103.38 is exposed, because the flaw is triggered just by loading a crafted page. Exploitation requires no account and no special setting. Teams that manage browsers for staff should check managed fleets, and browsers on shared kiosks or build agents count too.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"everyone","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: open the menu, go to Help > About Google Chrome, and let it update.","pkeys":[],"ptokens":[],"labels":["browsers","chrome","high","runtime","v8"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:31+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121221","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121221","severity":null,"published_at":"2026-11-03T21:17:31+00:00","modified_at":"2026-11-03T21:17:31+00:00","first_seen_at":"2026-11-03T21:19:27+00:00","fetched_at":"2026-11-03T21:19:27+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}