{"id":"CVE-2026-125244","kind":"vulnerability","aliases":["CVE-2026-125244"],"related":[],"title":"FFmpeg: crafted VVC video file overflows memory in decoder","description":"FFmpeg before 8.1.3 and 9.x before 9.0.2 contains an out-of-bounds write vulnerability in the VVC decoder's sh_entry_points() function in libavcodec/vvc/ps.c. Attackers can supply a crafted VVC (H.266) bitstream whose SPS/PPS tile and WPP layout produces excess entry points, overflowing entry_point_start_ctu and corrupting decoder memory.","summary":"FFmpeg's VVC (H.266) decoder writes past the end of a buffer when a crafted bitstream declares too many tile or WPP entry points. An attacker who supplies such a video file can corrupt decoder memory.","severity":"high","cvss":8.5,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ffmpeg","libavcodec","media-processing","package","self-hosted"],"not_affected_if":["no-vvc-decoding","trusted-input-only"],"how_to_check":"- Run `ffmpeg -version` and compare against the fixed versions below.\n- Check whether your FFmpeg build includes the VVC decoder (`ffmpeg -decoders | grep -i vvc`).","fix":"- FFmpeg `8.1.3` or later on the 8.x line\n- FFmpeg `9.0.2` or later on the 9.x line","status":"open","published_at":"2026-11-09T19:17:02+00:00","first_seen_at":"2026-11-09T19:28:20+00:00","triaged_at":"2026-11-09T19:29:29+00:00","updated_at":"2026-11-09T19:29:29+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-09T19:29:29Z","model":"claude-haiku-5-5","output":{"fix":"- FFmpeg `8.1.3` or later on the 8.x line\n- FFmpeg `9.0.2` or later on the 9.x line","reach":"unknown","title":"FFmpeg: crafted VVC video file overflows memory in decoder","impact":"high","summary":"FFmpeg's VVC (H.266) decoder writes past the end of a buffer when a crafted bitstream declares too many tile or WPP entry points. An attacker who supplies such a video file can corrupt decoder memory.","audience":"developers","category":"package","nicknames":[],"who_cares":["ffmpeg","libavcodec","media-processing","self-hosted"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"attacker corrupts decoder memory, possibly running code on the host","analyst_note":"Check the vulncheck advisory and the patch link to confirm the VVC decoder trigger and whether the code-execution impact is demonstrated.","how_to_check":"- Run `ffmpeg -version` and compare against the fixed versions below.\n- Check whether your FFmpeg build includes the VVC decoder (`ffmpeg -decoders | grep -i vvc`).","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["no-vvc-decoding","trusted-input-only"],"who_is_affected":"Systems that decode untrusted VVC/H.266 video with FFmpeg, such as media transcoding services, thumbnailers or upload pipelines. Applications that never decode VVC, or only process trusted media, are unlikely to be reachable.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000767,"input_tokens":4652,"output_tokens":604,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-125244':12A,15A '-2026':11A,14A '8.1.3':63C '9':65C '9.0.2':68C 'attack':50B,88C 'bitstream':40B,95C 'bound':74C 'buffer':36B 'contain':69C 'corrupt':58B,112C 'craft':2A,39B,92C 'ctu':110C 'cve':10A,13A 'declar':41B 'decod':9A,29B,59B,80C,113C 'end':33B 'entri':47B,83C,104C,107C 'excess':103C 'ffmpeg':1A,16B,25B,61C 'file':5A,56B 'function':85C 'h.266':28B,94C 'host':24B 'layout':101C 'libavcodec':17B 'libavcodec/vvc/ps.c':87C 'mani':43B 'media':19B 'media-process':18B 'memori':7A,60B,114C 'out-of-bound':71C 'overflow':6A,106C 'packag':21B 'past':31B 'point':48B,84C,105C,108C 'process':20B 'produc':102C 'self':23B 'self-host':22B 'sh':82C 'sps/pps':97C 'start':109C 'suppli':52B,90C 'tile':44B,98C 'video':4A,55B 'vulner':76C 'vvc':3A,27B,79C,93C 'whose':96C 'wpp':46B,100C 'write':30B,75C 'x':66C","nicknames":[],"mitigations":[],"who_affected":"Systems that decode untrusted VVC/H.266 video with FFmpeg, such as media transcoding services, thumbnailers or upload pipelines. Applications that never decode VVC, or only process trusted media, are unlikely to be reachable.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"developers","plain_action":null,"pkeys":[],"ptokens":[],"labels":["ffmpeg","high","libavcodec","mediaprocessing","package","selfhosted"],"campaign_type":null,"search_a":"'-125244':12A,15A '-2026':11A,14A 'craft':2A 'cve':10A,13A 'decod':9A 'ffmpeg':1A 'file':5A 'memori':7A 'overflow':6A 'video':4A 'vvc':3A","search_b":"'attack':50B 'bitstream':40B 'buffer':36B 'corrupt':58B 'craft':39B 'declar':41B 'decod':29B,59B 'end':33B 'entri':47B 'ffmpeg':16B,25B 'file':56B 'h.266':28B 'host':24B 'libavcodec':17B 'mani':43B 'media':19B 'media-process':18B 'memori':60B 'packag':21B 'past':31B 'point':48B 'process':20B 'self':23B 'self-host':22B 'suppli':52B 'tile':44B 'video':55B 'vvc':27B 'wpp':46B 'write':30B","search_c":"'8.1.3':63C '9':65C '9.0.2':68C 'attack':88C 'bitstream':95C 'bound':74C 'contain':69C 'corrupt':112C 'craft':92C 'ctu':110C 'decod':80C,113C 'entri':83C,104C,107C 'excess':103C 'ffmpeg':61C 'function':85C 'h.266':94C 'layout':101C 'libavcodec/vvc/ps.c':87C 'memori':114C 'out-of-bound':71C 'overflow':106C 'point':84C,105C,108C 'produc':102C 'sh':82C 'sps/pps':97C 'start':109C 'suppli':90C 'tile':98C 'vulner':76C 'vvc':79C,93C 'whose':96C 'wpp':100C 'write':75C 'x':66C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-09T19:17:02+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/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-2026-125244","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-125244","severity":null,"published_at":"2026-11-09T19:17:02+00:00","modified_at":"2026-11-09T19:17:02+00:00","first_seen_at":"2026-11-09T19:28:20+00:00","fetched_at":"2026-11-09T19:28:20+00:00","note":null}],"documents":[{"id":109378,"url":"https://github.com/FFmpeg/FFmpeg/commit/a809a784ec9ff9910161c6c9554a041941d6ccce","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":109379,"url":"https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-vvc-decoder-out-of-bounds-write-via-sh-entry-points","title":"Third-party advisory: www.vulncheck.com","kind":"advisory","source":"nvd","publisher":"research","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Third-party advisory: www.vulncheck.com"}],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}