{"id":"CVE-2026-121138","kind":"vulnerability","aliases":["CVE-2026-121138"],"related":[],"title":"Chrome: CORS discrepancy lets a crafted web page read cross-origin data","description":"Observable discrepancy in CORS 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: Low)","summary":"Google Chrome before 157.0.8103.38 has an observable discrepancy in its CORS handling. A remote attacker who gets a victim to open a crafted HTML page can obtain cross-origin data.","severity":"low","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","end-users","runtime"],"not_affected_if":["chrome-updated","non-chromium-browser"],"how_to_check":"- Open Chrome, go to Settings > About Chrome, and note the version\n- Check that the version is `157.0.8103.38` or later","fix":"- Google Chrome: `157.0.8103.38`","status":"open","published_at":"2026-11-03T21:17:22+00:00","first_seen_at":"2026-11-03T21:19:22+00:00","triaged_at":"2026-11-03T21:24:40+00:00","updated_at":"2026-11-03T21:24:40+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-11-03T21:24:40Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: `157.0.8103.38`","reach":"internet","title":"Chrome: CORS discrepancy lets a crafted web page read cross-origin data","impact":"low","summary":"Google Chrome before 157.0.8103.38 has an observable discrepancy in its CORS handling. A remote attacker who gets a victim to open a crafted HTML page can obtain cross-origin data.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","end-users"],"confidence":0.7,"fix_status":"available","needs_auth":"no","worst_case":"Cross-origin data from other sites is readable by the attacker","analyst_note":"","how_to_check":"- Open Chrome, go to Settings > About Chrome, and note the version\n- Check that the version is `157.0.8103.38` or later","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-updated","non-chromium-browser"],"who_is_affected":"Anyone running Google Chrome before 157.0.8103.38 who visits a page an attacker controls. Chromium-based browsers that have not picked up the fix are also exposed. Systems that do not use Chrome are not affected.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"low"},"cost_usd":0.00066,"input_tokens":4099,"output_tokens":500,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121138':16A,19A '-2026':15A,18A '157.0.8103.38':29B,66C 'allow':67C 'attack':40B,70C 'browser':20B 'chrome':1A,21B,27B,63C 'chromium':82C 'cor':2A,36B,60C 'craft':6A,48B,79C 'cross':11A,54B,74C 'cross-origin':10A,53B,73C 'cve':14A,17A 'data':13A,56B,76C 'discrep':3A,33B,58C 'end':23B 'end-us':22B 'get':42B 'googl':26B,62C 'handl':37B 'html':49B,80C 'let':4A 'low':85C 'observ':32B,57C 'obtain':52B,72C 'open':46B 'origin':12A,55B,75C 'page':8A,50B,81C 'prior':64C 'read':9A 'remot':39B,69C 'runtim':25B 'secur':83C 'sever':84C 'user':24B 'via':77C 'victim':44B 'web':7A","nicknames":[],"mitigations":[],"who_affected":"Anyone running Google Chrome before 157.0.8103.38 who visits a page an attacker controls. Chromium-based browsers that have not picked up the fix are also exposed. Systems that do not use Chrome are not 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","endusers","low","runtime"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:22+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121138","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121138","severity":null,"published_at":"2026-11-03T21:17:22+00:00","modified_at":"2026-11-03T21:17:22+00:00","first_seen_at":"2026-11-03T21:19:22+00:00","fetched_at":"2026-11-03T21:19:22+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"}