{"id":"CVE-2026-125223","kind":"vulnerability","aliases":["CVE-2026-125223"],"related":[],"title":"FFmpeg: VP9 decoder leaks memory on malformed streams, exhausting process memory","description":"FFmpeg 8.0 through 9.0.2 contains a memory leak vulnerability in the VP9 decoder that allows attackers to exhaust memory because vp9_decode_frame() skips resetting the CBS fragment on error paths. Attackers can supply a crafted VP9 stream with invalid tile sizes decoded with slice threading to leak packet buffers and units, exhausting memory in the decoding application.","summary":"FFmpeg versions 8.0 through 9.0.2 have a VP9 decoder bug where error paths skip resetting the CBS fragment, so packet buffers and units leak. A crafted VP9 stream with invalid tile sizes, decoded with slice threading, can exhaust memory in the decoding application.","severity":"medium","cvss":5.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ffmpeg","media-processing","package","self-hosted","vp9"],"not_affected_if":["no-vp9-decoding","other-versions","trusted-input-only"],"how_to_check":"- Run `ffmpeg -version` and compare against the affected range `8.0` through `9.0.2`.\n- Check whether VP9 decoding with slice threading is used on untrusted input.","fix":"- Move to a version after `9.0.2` that includes the upstream patch; the exact fixed version is unknown from the sources.","status":"open","published_at":"2026-11-09T19:16:59+00:00","first_seen_at":"2026-11-09T19:28:19+00:00","triaged_at":"2026-11-09T19:32:01+00:00","updated_at":"2026-11-09T19:32:01+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-09T19:32:01Z","model":"claude-haiku-5-5","output":{"fix":"- Move to a version after `9.0.2` that includes the upstream patch; the exact fixed version is unknown from the sources.","reach":"network","title":"FFmpeg: VP9 decoder leaks memory on malformed streams, exhausting process memory","impact":"low","summary":"FFmpeg versions 8.0 through 9.0.2 have a VP9 decoder bug where error paths skip resetting the CBS fragment, so packet buffers and units leak. A crafted VP9 stream with invalid tile sizes, decoded with slice threading, can exhaust memory in the decoding application.","audience":"businesses","category":"package","nicknames":[],"who_cares":["ffmpeg","vp9","media-processing","self-hosted"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"decoding process runs out of memory and crashes or stalls","analyst_note":"","how_to_check":"- Run `ffmpeg -version` and compare against the affected range `8.0` through `9.0.2`.\n- Check whether VP9 decoding with slice threading is used on untrusted input.","plain_action":"","product_name":"","needs_analyst":false,"not_affected_if":["trusted-input-only","other-versions","no-vp9-decoding"],"who_is_affected":"Systems that decode VP9 video from untrusted sources with FFmpeg 8.0 through 9.0.2, especially with slice threading enabled. Applications that only process trusted media or use other FFmpeg versions are not exposed by this flaw.","user_interaction":"no","product_ecosystem":"","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000745,"input_tokens":4641,"output_tokens":561,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-125223':14A,17A '-2026':13A,16A '8.0':29B,71C '9.0.2':31B,73C 'allow':84C 'applic':69B,127C 'attack':85C,101C 'buffer':47B,119C 'bug':36B 'cbs':43B,96C 'contain':74C 'craft':52B,105C 'cve':12A,15A 'decod':3A,35B,59B,68B,82C,91C,112C,126C 'error':38B,99C 'exhaust':9A,64B,87C,122C 'ffmpeg':1A,18B,27B,70C 'fragment':44B,97C 'frame':92C 'host':25B 'invalid':56B,109C 'leak':4A,50B,77C,117C 'malform':7A 'media':20B 'media-process':19B 'memori':5A,11A,65B,76C,88C,123C 'packag':22B 'packet':46B,118C 'path':39B,100C 'process':10A,21B 'reset':41B,94C 'self':24B 'self-host':23B 'size':58B,111C 'skip':40B,93C 'slice':61B,114C 'stream':8A,54B,107C 'suppli':103C 'thread':62B,115C 'tile':57B,110C 'unit':49B,121C 'version':28B 'vp9':2A,26B,34B,53B,81C,90C,106C 'vulner':78C","nicknames":[],"mitigations":[],"who_affected":"Systems that decode VP9 video from untrusted sources with FFmpeg 8.0 through 9.0.2, especially with slice threading enabled. Applications that only process trusted media or use other FFmpeg versions are not exposed by this flaw.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["ffmpeg","mediaprocessing","medium","package","selfhosted","vp9"],"campaign_type":null,"search_a":"'-125223':14A,17A '-2026':13A,16A 'cve':12A,15A 'decod':3A 'exhaust':9A 'ffmpeg':1A 'leak':4A 'malform':7A 'memori':5A,11A 'process':10A 'stream':8A 'vp9':2A","search_b":"'8.0':29B '9.0.2':31B 'applic':69B 'buffer':47B 'bug':36B 'cbs':43B 'craft':52B 'decod':35B,59B,68B 'error':38B 'exhaust':64B 'ffmpeg':18B,27B 'fragment':44B 'host':25B 'invalid':56B 'leak':50B 'media':20B 'media-process':19B 'memori':65B 'packag':22B 'packet':46B 'path':39B 'process':21B 'reset':41B 'self':24B 'self-host':23B 'size':58B 'skip':40B 'slice':61B 'stream':54B 'thread':62B 'tile':57B 'unit':49B 'version':28B 'vp9':26B,34B,53B","search_c":"'8.0':71C '9.0.2':73C 'allow':84C 'applic':127C 'attack':85C,101C 'buffer':119C 'cbs':96C 'contain':74C 'craft':105C 'decod':82C,91C,112C,126C 'error':99C 'exhaust':87C,122C 'ffmpeg':70C 'fragment':97C 'frame':92C 'invalid':109C 'leak':77C,117C 'memori':76C,88C,123C 'packet':118C 'path':100C 'reset':94C 'size':111C 'skip':93C 'slice':114C 'stream':107C 'suppli':103C 'thread':115C 'tile':110C 'unit':121C 'vp9':81C,90C,106C 'vulner':78C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-09T19:16:59+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:N/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-2026-125223","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-125223","severity":null,"published_at":"2026-11-09T19:16:59+00:00","modified_at":"2026-11-09T19:16:59+00:00","first_seen_at":"2026-11-09T19:28:19+00:00","fetched_at":"2026-11-09T19:28:19+00:00","note":null}],"documents":[{"id":109336,"url":"https://github.com/FFmpeg/FFmpeg/commit/bcce3232016695f5e482867519c45727a0a2a2c9","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":109337,"url":"https://www.vulncheck.com/advisories/ffmpeg-8.0-through-9.0.2-memory-leak-in-vp9-decoder-via-vp9-decode-frame","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"}