{"id":"CVE-2026-120210","kind":"vulnerability","aliases":["CVE-2026-120210"],"related":[],"title":"FFmpeg: crafted IMF package lets attackers open files outside the package","description":"FFmpeg 5.0 through 9.0.2 contains a path traversal vulnerability in the IMF demuxer that allows attackers to open files outside the package via unvalidated ASSETMAP Path elements. Attackers can supply a crafted IMF package with '..' or absolute paths to demux local MXF files, probe file existence and size, or trigger server-side requests.","summary":"FFmpeg's IMF demuxer trusts file paths listed in an ASSETMAP without checking them, so a crafted package can point at files outside its folder. An attacker can read local MXF files, probe whether files exist and how large they are, or make the server issue requests.","severity":"medium","cvss":5.3,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ffmpeg","media-processing","runtime","self-hosted"],"not_affected_if":["no-imf-input","trusted-input-only"],"how_to_check":"- Check the installed version with `ffmpeg -version`; affected releases are 5.0 through 9.0.2.\n- Find out whether the IMF demuxer is used on untrusted input, for example when media packages from users or external partners are processed.","fix":"- FFmpeg `9.0.2` and earlier in the range 5.0 through 9.0.2 are affected; the sources do not name the fixed version.","status":"open","published_at":"2026-10-31T18:17:09+00:00","first_seen_at":"2026-10-31T18:37:13+00:00","triaged_at":"2026-10-31T18:40:39+00:00","updated_at":"2026-10-31T18:40:39+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-10-31T18:40:39Z","model":"claude-haiku-5-5","output":{"fix":"- FFmpeg `9.0.2` and earlier in the range 5.0 through 9.0.2 are affected; the sources do not name the fixed version.","reach":"internet","title":"FFmpeg: crafted IMF package lets attackers open files outside the package","impact":"medium","summary":"FFmpeg's IMF demuxer trusts file paths listed in an ASSETMAP without checking them, so a crafted package can point at files outside its folder. An attacker can read local MXF files, probe whether files exist and how large they are, or make the server issue requests.","audience":"developers","category":"runtime","nicknames":[],"who_cares":["ffmpeg","media-processing","self-hosted"],"confidence":0.6,"fix_status":"unknown","needs_auth":"no","worst_case":"local files outside the package are read or probed","analyst_note":"Confirm the fixed FFmpeg version and whether the IMF demuxer is enabled by default, using the NVD entry and the FFmpeg project's release notes.","how_to_check":"- Check the installed version with `ffmpeg -version`; affected releases are 5.0 through 9.0.2.\n- Find out whether the IMF demuxer is used on untrusted input, for example when media packages from users or external partners are processed.","plain_action":"","needs_analyst":true,"not_affected_if":["no-imf-input","trusted-input-only"],"who_is_affected":"Teams that run FFmpeg and feed it IMF packages from sources they do not fully trust, such as media ingest pipelines or services that transcode uploads. Systems that only process their own media or never handle IMF packages are unlikely to be exposed.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000716,"input_tokens":4160,"output_tokens":600,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-120210':14A,17A '-2026':13A,16A '5.0':74C '9.0.2':76C 'absolut':109C 'allow':87C 'assetmap':36B,97C 'attack':6A,52B,88C,100C 'check':38B 'contain':77C 'craft':2A,42B,104C 'cve':12A,15A 'demux':29B,85C,112C 'element':99C 'exist':61B,118C 'ffmpeg':1A,18B,26B,73C 'file':8A,31B,47B,57B,60B,91C,115C,117C 'folder':50B 'host':25B 'imf':3A,28B,84C,105C 'issu':71B 'larg':64B 'let':5A 'list':33B 'local':55B,113C 'make':68B 'media':20B 'media-process':19B 'mxf':56B,114C 'open':7A,90C 'outsid':9A,48B,92C 'packag':4A,11A,43B,94C,106C 'path':32B,79C,98C,110C 'point':45B 'probe':58B,116C 'process':21B 'read':54B 'request':72B,126C 'runtim':22B 'self':24B 'self-host':23B 'server':70B,124C 'server-sid':123C 'side':125C 'size':120C 'suppli':102C 'travers':80C 'trigger':122C 'trust':30B 'unvalid':96C 'via':95C 'vulner':81C 'whether':59B 'without':37B","nicknames":[],"mitigations":[],"who_affected":"Teams that run FFmpeg and feed it IMF packages from sources they do not fully trust, such as media ingest pipelines or services that transcode uploads. Systems that only process their own media or never handle IMF packages are unlikely to be exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"unknown","audience":"developers","plain_action":null,"first_public_at":"2026-10-31T18:17:09+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-120210","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120210","severity":null,"published_at":"2026-10-31T18:17:09+00:00","modified_at":"2026-10-31T18:17:09+00:00","first_seen_at":"2026-10-31T18:37:13+00:00","fetched_at":"2026-10-31T18:37:13+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"}