{"id":"CVE-2026-117968","kind":"vulnerability","aliases":["CVE-2026-117968"],"related":[],"title":"Firefox: use-after-free in DOM core and HTML lets attackers run code","description":"Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.","summary":"A use-after-free bug in the DOM Core and HTML component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker gets beyond that, so the reach of the flaw is unconfirmed.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","desktop","firefox","package"],"not_affected_if":["already-on-fixed-version"],"how_to_check":"- Check the installed Firefox version in Help > About Firefox or with `firefox --version`, and compare it to the fixed releases.\n- Check ESR installs for `115.44` or `153.6` or later.","fix":"- Update Firefox to `159` or later.\n- Update Firefox ESR 115 to `115.44` or later.\n- Update Firefox ESR 153 to `153.6` or later.","status":"open","published_at":"2026-10-27T14:16:54+00:00","first_seen_at":"2026-10-27T14:32:24+00:00","triaged_at":"2026-10-27T14:35:21+00:00","updated_at":"2026-10-27T14:35:21+00:00","category":"package","confidence":0.5,"triage":{"at":"2026-10-27T14:35:21Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or later.\n- Update Firefox ESR 115 to `115.44` or later.\n- Update Firefox ESR 153 to `153.6` or later.","reach":"unknown","title":"Firefox: use-after-free in DOM core and HTML lets attackers run code","impact":"high","summary":"A use-after-free bug in the DOM Core and HTML component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker gets beyond that, so the reach of the flaw is unconfirmed.","category":"package","nicknames":[],"who_cares":["firefox","desktop","browsers"],"confidence":0.5,"needs_auth":"unknown","worst_case":"unknown, sources do not say what an attacker gets","analyst_note":"Check the Mozilla security advisory for CVE-2026-117968 to confirm the impact and whether web content alone can trigger it.","how_to_check":"- Check the installed Firefox version in Help > About Firefox or with `firefox --version`, and compare it to the fixed releases.\n- Check ESR installs for `115.44` or `153.6` or later.","needs_analyst":true,"not_affected_if":["already-on-fixed-version"],"who_is_affected":"Anyone running a Firefox build older than the fixed releases on desktops or managed fleets. The sources do not say whether the flaw is reachable from web content alone or needs a particular setting. Teams that only run the latest fixed release can skip it.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.0006,"input_tokens":3254,"output_tokens":550,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117968':17A,20A '-2026':16A,19A '115.44':86C '153.6':90C '159':83C 'attack':12A,55B 'beyond':57B 'browser':21B 'bug':30B 'code':14A 'compon':37B,76C 'core':8A,34B,74C 'cve':15A,18A 'desktop':22B 'dom':7A,33B,73C 'esr':85C,89C 'firefox':1A,23B,39B,82C,84C,88C 'fix':80C 'flaw':64B 'free':5A,29B,70C 'freed':47B 'get':56B 'html':10A,36B,75C 'let':11A,40B 'memori':41B 'packag':24B 'reach':61B 'reus':43B 'run':13A 'say':52B 'sourc':49B 'unconfirm':66B 'use':3A,27B,68C 'use-after-fre':2A,26B,67C 'vulner':78C","nicknames":[],"mitigations":[],"who_affected":"Anyone running a Firefox build older than the fixed releases on desktops or managed fleets. The sources do not say whether the flaw is reachable from web content alone or needs a particular setting. Teams that only run the latest fixed release can skip 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-2026-117968","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117968","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"}