{"id":"CVE-2026-117924","kind":"vulnerability","aliases":["CVE-2026-117924"],"related":[],"title":"Firefox: use-after-free in XSLT component fixed in several releases","description":"Use-after-free in the XSLT 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 XSLT component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker can do with it beyond that.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","desktop","firefox","runtime"],"not_affected_if":["already-updated"],"how_to_check":"- Check the installed Firefox version, for example in the About Firefox dialog or with `firefox --version`\n- Compare it with the fixed releases: `159`, `115.44` ESR, and `153.6` ESR\n- unknown for any other check","fix":"- Update Firefox to `159` or later on the current channel\n- Update Firefox ESR to `115.44` or `153.6` on the ESR channel\n- unknown for any other action","status":"open","published_at":"2026-10-27T14:16:48+00:00","first_seen_at":"2026-10-27T14:32:23+00:00","triaged_at":"2026-10-27T14:37:15+00:00","updated_at":"2026-10-27T14:37:15+00:00","category":"runtime","confidence":0.4,"triage":{"at":"2026-10-27T14:37:15Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or later on the current channel\n- Update Firefox ESR to `115.44` or `153.6` on the ESR channel\n- unknown for any other action","reach":"internet","title":"Firefox: use-after-free in XSLT component fixed in several releases","impact":"high","summary":"A use-after-free bug in the XSLT component of Firefox lets memory be reused after it is freed. The sources do not say what an attacker can do with it beyond that.","category":"runtime","nicknames":[],"who_cares":["firefox","browsers","desktop"],"confidence":0.4,"needs_auth":"unknown","worst_case":"unknown; memory corruption that could allow code execution is possible","analyst_note":"Check the Mozilla security advisory for CVE-2026-117924 to confirm the impact, trigger conditions and whether it is exploited, since the NVD entry gives only a one-line description.","how_to_check":"- Check the installed Firefox version, for example in the About Firefox dialog or with `firefox --version`\n- Compare it with the fixed releases: `159`, `115.44` ESR, and `153.6` ESR\n- unknown for any other check","needs_analyst":true,"not_affected_if":["already-updated"],"who_is_affected":"Anyone running a Firefox build older than the fixed releases can be affected, since the bug is in the browser's XSLT handling. The sources do not say whether a page or document must be opened to trigger it. unknown for whether server-side or embedded uses are affected.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000604,"input_tokens":3242,"output_tokens":559,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117924':15A,18A '-2026':14A,17A '115.44':73C '153.6':77C '159':70C 'attack':50B 'beyond':55B 'browser':19B 'bug':28B 'compon':8A,32B,63C 'cve':13A,16A 'desktop':20B 'esr':72C,76C 'firefox':1A,21B,34B,69C,71C,75C 'fix':9A,67C 'free':5A,27B,59C 'freed':42B 'let':35B 'memori':36B 'releas':12A 'reus':38B 'runtim':22B 'say':47B 'sever':11A 'sourc':44B 'use':3A,25B,57C 'use-after-fre':2A,24B,56C 'vulner':65C 'xslt':7A,31B,62C","nicknames":[],"mitigations":[],"who_affected":"Anyone running a Firefox build older than the fixed releases can be affected, since the bug is in the browser's XSLT handling. The sources do not say whether a page or document must be opened to trigger it. unknown for whether server-side or embedded uses are affected.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T14:16:48+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-117924","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117924","severity":null,"published_at":"2026-10-27T14:16:48+00:00","modified_at":"2026-10-27T14:16:48+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"}