{"id":"CVE-2026-121212","kind":"vulnerability","aliases":["CVE-2026-121212"],"related":[],"title":"Chrome: incorrect authorization lets a crafted page bypass web origin policy","description":"Incorrect authorization in Core in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: Medium)","summary":"Google Chrome before 157.0.8103.38 has an authorization flaw in its Core component. A remote attacker can use a crafted HTML page to bypass web origin policy, which can expose data from other sites.","severity":"medium","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","desktop","runtime"],"not_affected_if":["chrome-up-to-date"],"how_to_check":"- Check the installed Chrome version in Chrome's About page or with `google-chrome --version` on Linux.\n- Confirm whether managed browsers on the fleet are below `157.0.8103.38`.","fix":"- Google Chrome: move to `157.0.8103.38` or later.","status":"open","published_at":"2026-11-03T21:17:30+00:00","first_seen_at":"2026-11-03T21:19:26+00:00","triaged_at":"2026-11-03T21:22:37+00:00","updated_at":"2026-11-03T21:22:37+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-11-03T21:22:37Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later.","reach":"internet","title":"Chrome: incorrect authorization lets a crafted page bypass web origin policy","impact":"medium","summary":"Google Chrome before 157.0.8103.38 has an authorization flaw in its Core component. A remote attacker can use a crafted HTML page to bypass web origin policy, which can expose data from other sites.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","desktop"],"confidence":0.7,"fix_status":"available","needs_auth":"no","worst_case":"Attacker page reads cross-origin data in the victim's browser.","analyst_note":"","how_to_check":"- Check the installed Chrome version in Chrome's About page or with `google-chrome --version` on Linux.\n- Confirm whether managed browsers on the fleet are below `157.0.8103.38`.","plain_action":"Update Google Chrome to version 157.0.8103.38 or later through the browser's update menu.","needs_analyst":false,"not_affected_if":["chrome-up-to-date"],"who_is_affected":"Anyone running Google Chrome before 157.0.8103.38 who visits a page an attacker controls. Managed fleets running older builds are the main concern for businesses. Users on current Chrome builds are not affected.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000664,"input_tokens":4098,"output_tokens":509,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121212':14A,17A '-2026':13A,16A '157.0.8103.38':25B,64C 'allow':65C 'attack':36B,68C 'author':3A,28B,56C 'browser':18B 'bypass':8A,44B,70C 'chrome':1A,19B,23B,61C 'chromium':79C 'compon':33B 'core':32B,58C 'craft':6A,40B,76C 'cve':12A,15A 'data':51B 'desktop':20B 'expos':50B 'flaw':29B 'googl':22B,60C 'html':41B,77C 'incorrect':2A,55C 'let':4A 'medium':82C 'origin':10A,46B,72C 'page':7A,42B,78C 'polici':11A,47B,73C 'prior':62C 'remot':35B,67C 'runtim':21B 'secur':80C 'sever':81C 'site':54B 'use':38B 'via':74C 'web':9A,45B,71C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Google Chrome before 157.0.8103.38 who visits a page an attacker controls. Managed fleets running older builds are the main concern for businesses. Users on current Chrome builds 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 through the browser's update menu.","pkeys":[],"ptokens":[],"labels":["browsers","chrome","desktop","medium","runtime"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:30+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121212","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121212","severity":null,"published_at":"2026-11-03T21:17:30+00:00","modified_at":"2026-11-03T21:17:30+00:00","first_seen_at":"2026-11-03T21:19:26+00:00","fetched_at":"2026-11-03T21:19:26+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"}