{"id":"CVE-2026-117911","kind":"vulnerability","aliases":["CVE-2026-117911"],"related":[],"title":"Firefox: use-after-free in audio and video playback component","description":"Use-after-free in the Audio/Video: Playback 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 Audio/Video Playback component frees memory that is still used later. An attacker who gets a user to load crafted media could potentially crash the browser or run code in it.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","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`; affected builds are older than `159` on the main branch, `115.44` on ESR 115, and `153.6` on ESR 153.","fix":"- Update Firefox to `159` or later, or Firefox ESR to `115.44` or `153.6`, depending on the channel in use.","status":"open","published_at":"2026-10-27T14:16:46+00:00","first_seen_at":"2026-10-27T14:32:22+00:00","triaged_at":"2026-10-27T14:37:27+00:00","updated_at":"2026-10-27T14:37:27+00:00","category":"runtime","confidence":0.5,"triage":{"at":"2026-10-27T14:37:27Z","model":"claude-haiku-5-5","output":{"fix":"- Update Firefox to `159` or later, or Firefox ESR to `115.44` or `153.6`, depending on the channel in use.","reach":"internet","title":"Firefox: use-after-free in audio and video playback component","impact":"high","summary":"A use-after-free bug in Firefox's Audio/Video Playback component frees memory that is still used later. An attacker who gets a user to load crafted media could potentially crash the browser or run code in it.","category":"runtime","nicknames":[],"who_cares":["firefox","desktop","browsers"],"confidence":0.5,"needs_auth":"unknown","worst_case":"unknown; code execution in the browser process is possible for use-after-free bugs","analyst_note":"Check the Mozilla security advisory for CVE-2026-117911 for the impact rating, trigger conditions and whether exploitation is known; the NVD entry gave no severity.","how_to_check":"- Check the installed Firefox version in the About Firefox dialog or with `firefox --version`; affected builds are older than `159` on the main branch, `115.44` on ESR 115, and `153.6` on ESR 153.","needs_analyst":true,"not_affected_if":["fixed-version"],"who_is_affected":"Anyone running Firefox builds from before the fixed versions, on desktop or in managed fleets that have not pushed the update. Systems on a fixed version are not affected. The sources do not say whether the bug is reachable without user interaction.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000594,"input_tokens":3254,"output_tokens":537,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-117911':14A,17A '-2026':13A,16A '115.44':77C '153.6':81C '159':74C 'attack':42B 'audio':7A 'audio/video':31B,65C 'browser':18B,55B 'bug':27B 'code':58B 'compon':11A,33B,67C 'could':51B 'craft':49B 'crash':53B 'cve':12A,15A 'desktop':19B 'esr':76C,80C 'firefox':1A,20B,29B,73C,75C,79C 'fix':71C 'free':5A,26B,34B,62C 'get':44B 'later':40B 'load':48B 'media':50B 'memori':35B 'playback':10A,32B,66C 'potenti':52B 'run':57B 'runtim':21B 'still':38B 'use':3A,24B,39B,60C 'use-after-fre':2A,23B,59C 'user':46B 'video':9A 'vulner':69C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Firefox builds from before the fixed versions, on desktop or in managed fleets that have not pushed the update. Systems on a fixed version are not affected. The sources do not say whether the bug is reachable without user interaction.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T14:16:46+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-117911","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-117911","severity":null,"published_at":"2026-10-27T14:16:46+00:00","modified_at":"2026-10-27T14:16:46+00:00","first_seen_at":"2026-10-27T14:32:22+00:00","fetched_at":"2026-10-27T14:32:22+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"}