{"id":"CVE-2026-121198","kind":"vulnerability","aliases":["CVE-2026-121198"],"related":[],"title":"Chrome: WebUI confused deputy lets crafted page bypass origin policy","description":"Confused deputy in WebUI in Google Chrome prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to bypass web origin policy via a crafted HTML page. (Chromium security severity: Low)","summary":"A confused deputy flaw in the WebUI of Google Chrome before 157.0.8103.38 lets a remote attacker bypass web origin policy using a crafted HTML page. Chromium rates it Low severity and it needs social engineering to lure a user to the page.","severity":"low","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","endpoints","runtime"],"not_affected_if":["chrome-up-to-date"],"how_to_check":"- Check the installed Chrome version in the browser's About page or with `chrome://version`.\n- Confirm the version is below `157.0.8103.38`.","fix":"- Google Chrome: move to `157.0.8103.38` or later.","status":"open","published_at":"2026-11-03T21:17:28+00:00","first_seen_at":"2026-11-03T21:19:25+00:00","triaged_at":"2026-11-03T21:22:53+00:00","updated_at":"2026-11-03T21:22:53+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-11-03T21:22:53Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later.","reach":"internet","title":"Chrome: WebUI confused deputy lets crafted page bypass origin policy","impact":"medium","summary":"A confused deputy flaw in the WebUI of Google Chrome before 157.0.8103.38 lets a remote attacker bypass web origin policy using a crafted HTML page. Chromium rates it Low severity and it needs social engineering to lure a user to the page.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","endpoints"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"Crafted page bypasses origin policy in browser WebUI pages","analyst_note":"","how_to_check":"- Check the installed Chrome version in the browser's About page or with `chrome://version`.\n- Confirm the version is below `157.0.8103.38`.","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: Chrome menu > Help > About Google Chrome.","needs_analyst":false,"not_affected_if":["chrome-up-to-date"],"who_is_affected":"Anyone running Google Chrome older than 157.0.8103.38 is exposed, as the attack needs a user to visit a crafted HTML page. Managed or auto-updated browsers are likely already current; the sources do not say whether other Chromium-based browsers are affected.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"low"},"cost_usd":0.000682,"input_tokens":4105,"output_tokens":542,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121198':13A,16A '-2026':12A,15A '157.0.8103.38':32B,72C 'allow':73C 'attack':36B,76C 'browser':17B 'bypass':8A,37B,81C 'chrome':1A,18B,30B,69C 'chromium':46B,90C 'confus':3A,22B,63C 'craft':6A,43B,87C 'cve':11A,14A 'deputi':4A,23B,64C 'endpoint':19B 'engin':55B,79C 'flaw':24B 'googl':29B,68C 'html':44B,88C 'let':5A,33B 'leverag':77C 'low':49B,93C 'lure':57B 'need':53B 'origin':9A,39B,83C 'page':7A,45B,62B,89C 'polici':10A,40B,84C 'prior':70C 'rate':47B 'remot':35B,75C 'runtim':20B 'secur':91C 'sever':50B,92C 'social':54B,78C 'use':41B 'user':59B 'via':85C 'web':38B,82C 'webui':2A,27B,66C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Google Chrome older than 157.0.8103.38 is exposed, as the attack needs a user to visit a crafted HTML page. Managed or auto-updated browsers are likely already current; the sources do not say whether other Chromium-based browsers are affected.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"everyone","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: Chrome menu > Help > About Google Chrome.","pkeys":[],"ptokens":[],"labels":["browsers","chrome","endpoints","low","runtime"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:28+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121198","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121198","severity":null,"published_at":"2026-11-03T21:17:28+00:00","modified_at":"2026-11-03T21:17:28+00:00","first_seen_at":"2026-11-03T21:19:25+00:00","fetched_at":"2026-11-03T21:19:25+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"}