{"id":"CVE-2026-125174","kind":"vulnerability","aliases":["CVE-2026-125174"],"related":[],"title":"FFmpeg: crafted Hap video frame crashes decoder through NULL pointer","description":"FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a NULL pointer dereference vulnerability in ff_hap_set_chunk_count() in libavcodec/hap.c, where a shadowed return variable masks reallocation failures. Attackers can supply a crafted Hap video frame with an oversized chunk count so the decoder writes through a NULL chunk table, crashing the application.","summary":"FFmpeg's Hap video decoder mishandles a failed memory reallocation when a frame declares an oversized chunk count, leaving a NULL table that gets written to. An attacker who supplies a crafted Hap video file can crash the application that decodes it.","severity":"medium","cvss":6.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ffmpeg","libavcodec","media-processing","package"],"not_affected_if":["ffmpeg-before-8.0-or-not-in-range","no-hap-decoding"],"how_to_check":"- Check the FFmpeg version with `ffmpeg -version`, or the libavcodec version your application links against.\n- Look for FFmpeg or libavcodec in your dependency lists and container images.","fix":"- FFmpeg `8.1.3` for the 8.x line\n- FFmpeg `9.0.2` for the 9.x line","status":"open","published_at":"2026-11-09T19:16:52+00:00","first_seen_at":"2026-11-09T19:28:16+00:00","triaged_at":"2026-11-09T19:31:38+00:00","updated_at":"2026-11-09T19:31:38+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-09T19:31:38Z","model":"claude-haiku-5-5","output":{"fix":"- FFmpeg `8.1.3` for the 8.x line\n- FFmpeg `9.0.2` for the 9.x line","reach":"unknown","title":"FFmpeg: crafted Hap video frame crashes decoder through NULL pointer","impact":"low","summary":"FFmpeg's Hap video decoder mishandles a failed memory reallocation when a frame declares an oversized chunk count, leaving a NULL table that gets written to. An attacker who supplies a crafted Hap video file can crash the application that decodes it.","audience":"businesses","category":"package","nicknames":[],"who_cares":["ffmpeg","libavcodec","media-processing"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"Application crashes while decoding a malicious video file","analyst_note":"","how_to_check":"- Check the FFmpeg version with `ffmpeg -version`, or the libavcodec version your application links against.\n- Look for FFmpeg or libavcodec in your dependency lists and container images.","plain_action":"","product_name":"","needs_analyst":false,"not_affected_if":["no-hap-decoding","FFmpeg-before-8.0-or-not-in-range"],"who_is_affected":"Any application that decodes Hap-encoded video with FFmpeg's libavcodec, including media pipelines and transcoding services that accept user-supplied files. Systems that never decode Hap video or that use FFmpeg builds without the Hap decoder are not affected.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000748,"input_tokens":4634,"output_tokens":570,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-125174':13A,16A '-2026':12A,15A '8.1.3':66C '9':68C '9.0.2':71C 'applic':61B,118C 'attack':50B,94C 'chunk':39B,82C,105C,114C 'contain':72C 'count':40B,83C,106C 'craft':2A,54B,98C 'crash':6A,59B,116C 'cve':11A,14A 'declar':36B 'decod':7A,27B,63B,109C 'derefer':76C 'fail':30B 'failur':93C 'ff':79C 'ffmpeg':1A,17B,23B,64C 'file':57B 'frame':5A,35B,101C 'get':46B 'hap':3A,25B,55B,80C,99C 'leav':41B 'libavcodec':18B 'libavcodec/hap.c':85C 'mask':91C 'media':20B 'media-process':19B 'memori':31B 'mishandl':28B 'null':9A,43B,74C,113C 'overs':38B,104C 'packag':22B 'pointer':10A,75C 'process':21B 'realloc':32B,92C 'return':89C 'set':81C 'shadow':88C 'suppli':52B,96C 'tabl':44B,115C 'variabl':90C 'video':4A,26B,56B,100C 'vulner':77C 'write':110C 'written':47B 'x':69C","nicknames":[],"mitigations":[],"who_affected":"Any application that decodes Hap-encoded video with FFmpeg's libavcodec, including media pipelines and transcoding services that accept user-supplied files. Systems that never decode Hap video or that use FFmpeg builds without the Hap decoder are not affected.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["ffmpeg","libavcodec","mediaprocessing","medium","package"],"campaign_type":null,"search_a":"'-125174':13A,16A '-2026':12A,15A 'craft':2A 'crash':6A 'cve':11A,14A 'decod':7A 'ffmpeg':1A 'frame':5A 'hap':3A 'null':9A 'pointer':10A 'video':4A","search_b":"'applic':61B 'attack':50B 'chunk':39B 'count':40B 'craft':54B 'crash':59B 'declar':36B 'decod':27B,63B 'fail':30B 'ffmpeg':17B,23B 'file':57B 'frame':35B 'get':46B 'hap':25B,55B 'leav':41B 'libavcodec':18B 'media':20B 'media-process':19B 'memori':31B 'mishandl':28B 'null':43B 'overs':38B 'packag':22B 'process':21B 'realloc':32B 'suppli':52B 'tabl':44B 'video':26B,56B 'written':47B","search_c":"'8.1.3':66C '9':68C '9.0.2':71C 'applic':118C 'attack':94C 'chunk':82C,105C,114C 'contain':72C 'count':83C,106C 'craft':98C 'crash':116C 'decod':109C 'derefer':76C 'failur':93C 'ff':79C 'ffmpeg':64C 'frame':101C 'hap':80C,99C 'libavcodec/hap.c':85C 'mask':91C 'null':74C,113C 'overs':104C 'pointer':75C 'realloc':92C 'return':89C 'set':81C 'shadow':88C 'suppli':96C 'tabl':115C 'variabl':90C 'video':100C 'vulner':77C 'write':110C 'x':69C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-09T19:16:52+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/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-2026-125174","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-125174","severity":null,"published_at":"2026-11-09T19:16:52+00:00","modified_at":"2026-11-09T19:16:52+00:00","first_seen_at":"2026-11-09T19:28:16+00:00","fetched_at":"2026-11-09T19:28:16+00:00","note":null}],"documents":[{"id":109235,"url":"https://github.com/FFmpeg/FFmpeg/commit/f8c4c6400e835bf65e8b9cc12aba9e5c4d1c818c","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":109236,"url":"https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-null-pointer-dereference-via-ff-hap-set-chunk-count","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"}