{"id":"CVE-2026-117937","kind":"vulnerability","aliases":["CVE-2026-117937"],"related":[],"title":"Firefox: invalid pointer in JavaScript engine fixed in version 159","description":"Invalid pointer in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.","summary":"Firefox's JavaScript engine mishandles a pointer, which is a memory-safety bug. The sources do not say what an attacker can achieve with it, and the description gives no severity.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browser","desktop","firefox","runtime"],"not_affected_if":["fixed-version"],"how_to_check":"- Check the installed Firefox version in the About Firefox dialog or with `firefox --version`; versions below `159`, `115.44` (ESR), or `153.6` (ESR) are affected.","fix":"- Update Firefox to `159` or later, or to ESR `115.44` or `153.6`.","status":"open","published_at":"2026-10-27T14:16:49+00:00","first_seen_at":"2026-10-27T14:32:23+00:00","triaged_at":"2026-10-27T14:36:58+00:00","updated_at":"2026-10-27T14:36:58+00:00","category":"runtime","confidence":0.5,"triage":{"at":"2026-10-27T14:36:58Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or later, or to ESR `115.44` or `153.6`.","reach":"internet","title":"Firefox: invalid pointer in JavaScript engine fixed in version 159","impact":"high","summary":"Firefox's JavaScript engine mishandles a pointer, which is a memory-safety bug. The sources do not say what an attacker can achieve with it, and the description gives no severity.","category":"runtime","nicknames":[],"who_cares":["firefox","desktop","browser"],"confidence":0.5,"needs_auth":"unknown","worst_case":"unknown; memory corruption in the browser engine, impact not stated","analyst_note":"Check the Mozilla security advisory for CVE-2026-117937 for severity, trigger conditions and whether it is exploited, since the NVD entry gives none of these.","how_to_check":"- Check the installed Firefox version in the About Firefox dialog or with `firefox --version`; versions below `159`, `115.44` (ESR), or `153.6` (ESR) are affected.","needs_analyst":true,"not_affected_if":["fixed-version"],"who_is_affected":"Anyone running Firefox builds older than the fixed releases, on desktop or in ESR deployments. The sources do not say whether the flaw needs a particular page or setting to trigger. Teams that run only the fixed versions can skip it.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000581,"input_tokens":3252,"output_tokens":512,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117937':13A,16A '-2026':12A,15A '115.44':69C '153.6':73C '159':10A,66C 'achiev':44B 'attack':42B 'browser':17B 'bug':34B 'compon':59C 'cve':11A,14A 'descript':49B 'desktop':18B 'engin':6A,24B,58C 'esr':68C,72C 'firefox':1A,19B,21B,65C,67C,71C 'fix':7A,63C 'give':50B 'invalid':2A,53C 'javascript':5A,23B,57C 'memori':32B 'memory-safeti':31B 'mishandl':25B 'pointer':3A,27B,54C 'runtim':20B 'safeti':33B 'say':39B 'sever':52B 'sourc':36B 'version':9A 'vulner':61C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Firefox builds older than the fixed releases, on desktop or in ESR deployments. The sources do not say whether the flaw needs a particular page or setting to trigger. Teams that run only the fixed versions can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T14:16:49+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-117937","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117937","severity":null,"published_at":"2026-10-27T14:16:49+00:00","modified_at":"2026-10-27T14:16:49+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"}