{"id":"CVE-2026-121255","kind":"vulnerability","aliases":["CVE-2026-121255"],"related":[],"title":"Chrome: Autofill AI flaw lets a crafted web page read cross-origin data","description":"Incorrect authorization in Autofill AI in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to obtain cross-origin data via a crafted HTML page. (Chromium security severity: Medium)","summary":"Google Chrome's Autofill AI feature had an incorrect authorization check before version 157.0.8103.38. A remote attacker who lures a user to a crafted HTML page can obtain data from other origins.","severity":"medium","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browser","chrome","end-users","other"],"not_affected_if":["chrome-updated"],"how_to_check":"- Check the Chrome version under Chrome menu > Help > About Google Chrome, or run `chrome://version` in the address bar.\n- Confirm whether Autofill AI is enabled in Chrome settings (unknown whether it is on by default).","fix":"- Google Chrome: move to `157.0.8103.38` or later.","status":"open","published_at":"2026-11-03T21:17:36+00:00","first_seen_at":"2026-11-03T21:19:29+00:00","triaged_at":"2026-11-03T21:20:54+00:00","updated_at":"2026-11-03T21:20:54+00:00","category":"other","confidence":0.6,"triage":{"at":"2026-11-03T21:20:54Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later.","reach":"internet","title":"Chrome: Autofill AI flaw lets a crafted web page read cross-origin data","impact":"medium","summary":"Google Chrome's Autofill AI feature had an incorrect authorization check before version 157.0.8103.38. A remote attacker who lures a user to a crafted HTML page can obtain data from other origins.","audience":"everyone","category":"other","nicknames":[],"who_cares":["chrome","browser","end-users"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"Cross-origin data from other sites is readable by an attacker's page.","analyst_note":"","how_to_check":"- Check the Chrome version under Chrome menu > Help > About Google Chrome, or run `chrome://version` in the address bar.\n- Confirm whether Autofill AI is enabled in Chrome settings (unknown whether it is on by default).","plain_action":"Update Google Chrome to version 157.0.8103.38 or later.","needs_analyst":false,"not_affected_if":["chrome-updated"],"who_is_affected":"Any Chrome installation older than 157.0.8103.38 may be exposed when a user visits a malicious page. Exposure to the Autofill AI feature specifically is unknown from the sources; managed or non-Chrome browsers are not described as affected.","user_interaction":"yes","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000674,"input_tokens":4106,"output_tokens":526,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121255':17A,20A '-2026':16A,19A '157.0.8103.38':39B,68C 'ai':3A,30B,62C 'allow':69C 'attack':42B,72C 'author':35B,59C 'autofil':2A,29B,61C 'browser':21B 'check':36B 'chrome':1A,22B,27B,65C 'chromium':84C 'craft':7A,49B,81C 'cross':12A,76C 'cross-origin':11A,75C 'cve':15A,18A 'data':14A,54B,78C 'end':24B 'end-us':23B 'featur':31B 'flaw':4A 'googl':26B,64C 'html':50B,82C 'incorrect':34B,58C 'let':5A 'lure':44B 'medium':87C 'obtain':53B,74C 'origin':13A,57B,77C 'page':9A,51B,83C 'prior':66C 'read':10A 'remot':41B,71C 'secur':85C 'sever':86C 'user':25B,46B 'version':38B 'via':79C 'web':8A","nicknames":[],"mitigations":[],"who_affected":"Any Chrome installation older than 157.0.8103.38 may be exposed when a user visits a malicious page. Exposure to the Autofill AI feature specifically is unknown from the sources; managed or non-Chrome browsers are not described as 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.","pkeys":[],"ptokens":[],"labels":["browser","chrome","endusers","medium","other"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:36+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121255","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121255","severity":null,"published_at":"2026-11-03T21:17:36+00:00","modified_at":"2026-11-03T21:17:36+00:00","first_seen_at":"2026-11-03T21:19:29+00:00","fetched_at":"2026-11-03T21:19:29+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"}