{"id":"CVE-2026-117944","kind":"vulnerability","aliases":["CVE-2026-117944"],"related":[],"title":"Firefox: use-after-free in Layout component may allow code execution","description":"Use-after-free in the Layout component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.","summary":"A use-after-free bug in Firefox's Layout component lets memory be reused after it is freed. The sources do not say what an attacker gets beyond that, so impact is unclear.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["desktop-browsers","esr","firefox","runtime"],"not_affected_if":["already-updated"],"how_to_check":"- Check the Firefox version with `about:support` in the browser menu and compare it with the fixed releases\n- unknown for any other check, the sources do not say","fix":"- Update Firefox to `159` or later\n- Update Firefox ESR to `115.44` or later on the 115 branch\n- Update Firefox ESR to `153.6` or later on the 153 branch","status":"open","published_at":"2026-10-27T14:16:50+00:00","first_seen_at":"2026-10-27T14:32:23+00:00","triaged_at":"2026-10-27T14:35:44+00:00","updated_at":"2026-10-27T14:35:44+00:00","category":"runtime","confidence":0.5,"triage":{"at":"2026-10-27T14:35:44Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or later\n- Update Firefox ESR to `115.44` or later on the 115 branch\n- Update Firefox ESR to `153.6` or later on the 153 branch","reach":"unknown","title":"Firefox: use-after-free in Layout component may allow code execution","impact":"high","summary":"A use-after-free bug in Firefox's Layout component lets memory be reused after it is freed. The sources do not say what an attacker gets beyond that, so impact is unclear.","category":"runtime","nicknames":[],"who_cares":["firefox","desktop-browsers","esr"],"confidence":0.5,"needs_auth":"unknown","worst_case":"unknown; use-after-free can allow memory corruption in the browser","analyst_note":"Check Mozilla's security advisory for this CVE to confirm exploitability, attack trigger and whether it is exploited in the wild.","how_to_check":"- Check the Firefox version with `about:support` in the browser menu and compare it with the fixed releases\n- unknown for any other check, the sources do not say","needs_analyst":true,"not_affected_if":["already-updated"],"who_is_affected":"Anyone running Firefox builds older than the fixed releases, on desktop or in ESR deployments. The sources do not say which configurations or content are needed to trigger it, so unknown.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000576,"input_tokens":3240,"output_tokens":503,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117944':15A,18A '-2026':14A,17A '115.44':76C '153.6':80C '159':73C 'allow':10A 'attack':51B 'beyond':53B 'browser':21B 'bug':30B 'code':11A 'compon':8A,35B,66C 'cve':13A,16A 'desktop':20B 'desktop-brows':19B 'esr':22B,75C,79C 'execut':12A 'firefox':1A,23B,32B,72C,74C,78C 'fix':70C 'free':5A,29B,62C 'freed':43B 'get':52B 'impact':56B 'layout':7A,34B,65C 'let':36B 'may':9A 'memori':37B 'reus':39B 'runtim':24B 'say':48B 'sourc':45B 'unclear':58B 'use':3A,27B,60C 'use-after-fre':2A,26B,59C 'vulner':68C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Firefox builds older than the fixed releases, on desktop or in ESR deployments. The sources do not say which configurations or content are needed to trigger it, so unknown.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T14:16:50+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-117944","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117944","severity":null,"published_at":"2026-10-27T14:16:50+00:00","modified_at":"2026-10-27T14:16:50+00:00","first_seen_at":"2026-10-27T14:32:23+00:00","fetched_at":"2026-10-27T14:32:23+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"}