{"id":"CVE-2026-117967","kind":"vulnerability","aliases":["CVE-2026-117967"],"related":[],"title":"Firefox: DOM security component mitigation bypass, fixed in Firefox 159","description":"Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 159 and Firefox ESR 153.6.","summary":"A flaw in the DOM Security component of Firefox lets a page get around a security mitigation. The sources do not say what an attacker can do after bypassing it.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","desktop","firefox","runtime"],"not_affected_if":["already-on-fixed-version"],"how_to_check":"- Run `firefox --version` or check About Firefox and compare against `159` or `153.6` for ESR.","fix":"- Update Firefox to `159` or Firefox ESR to `153.6`.","status":"open","published_at":"2026-10-27T14:16:54+00:00","first_seen_at":"2026-10-27T14:32:24+00:00","triaged_at":"2026-10-27T14:35:22+00:00","updated_at":"2026-10-27T14:35:22+00:00","category":"runtime","confidence":0.4,"triage":{"at":"2026-10-27T14:35:22Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or Firefox ESR to `153.6`.","reach":"internet","title":"Firefox: DOM security component mitigation bypass, fixed in Firefox 159","impact":"medium","summary":"A flaw in the DOM Security component of Firefox lets a page get around a security mitigation. The sources do not say what an attacker can do after bypassing it.","category":"runtime","nicknames":[],"who_cares":["firefox","browsers","desktop"],"confidence":0.4,"needs_auth":"unknown","worst_case":"unknown; sources do not describe the impact","analyst_note":"Check the Mozilla security advisory for this CVE to learn the exploit impact and whether user interaction is needed.","how_to_check":"- Run `firefox --version` or check About Firefox and compare against `159` or `153.6` for ESR.","needs_analyst":true,"not_affected_if":["already-on-fixed-version"],"who_is_affected":"Anyone running a Firefox build older than 159 or ESR older than 153.6 is potentially affected. The sources do not say whether specific configurations or content are needed to trigger it.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000541,"input_tokens":3238,"output_tokens":434,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117967':13A,16A '-2026':12A,15A '153.6':67C '159':10A,63C 'around':34B 'attack':45B 'browser':17B 'bypass':6A,49B,51C 'compon':4A,27B,56C 'cve':11A,14A 'desktop':18B 'dom':2A,25B,54C 'esr':66C 'firefox':1A,9A,19B,29B,62C,65C 'fix':7A,60C 'flaw':22B 'get':33B 'let':30B 'mitig':5A,37B,50C 'page':32B 'runtim':20B 'say':42B 'secur':3A,26B,36B,55C 'sourc':39B 'vulner':58C","nicknames":[],"mitigations":[],"who_affected":"Anyone running a Firefox build older than 159 or ESR older than 153.6 is potentially affected. The sources do not say whether specific configurations or content are needed to trigger it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T14:16:54+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-117967","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117967","severity":null,"published_at":"2026-10-27T14:16:54+00:00","modified_at":"2026-10-27T14:16:54+00:00","first_seen_at":"2026-10-27T14:32:24+00:00","fetched_at":"2026-10-27T14:32:24+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"}