{"id":"CVE-2026-125234","kind":"vulnerability","aliases":["CVE-2026-125234"],"related":[],"title":"FFmpeg: integer overflow in WavPack encoder hangs transcoding on crafted WAV","description":"FFmpeg through 9.0.2 contains an integer overflow vulnerability in wavpack_encode_init() in libavcodec/wavpackenc.c that causes an infinite loop when computing block size from sample rate and channel count. Attackers can supply a crafted audio file, such as a WAV header declaring a huge sample rate with many channels, to hang applications transcoding to WavPack.","summary":"FFmpeg's WavPack encoder computes a block size from sample rate and channel count with an integer overflow, which can cause an infinite loop. A crafted audio file with a large declared sample rate and many channels can hang an application that transcodes it to WavPack.","severity":"medium","cvss":6.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["audio-transcoding","ffmpeg","libavcodec","package","wavpack"],"not_affected_if":["no-wavpack-encoding","trusted-input-only"],"how_to_check":"- Check whether your application or service uses FFmpeg (libavcodec) to encode WavPack audio.\n- Check the installed FFmpeg version with `ffmpeg -version`; the sources say the flaw affects versions through `9.0.2`.","fix":null,"status":"open","published_at":"2026-11-09T19:17:01+00:00","first_seen_at":"2026-11-09T19:28:20+00:00","triaged_at":"2026-11-09T19:30:26+00:00","updated_at":"2026-11-09T19:30:26+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-09T19:30:26Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"unknown","title":"FFmpeg: integer overflow in WavPack encoder hangs transcoding on crafted WAV","impact":"low","summary":"FFmpeg's WavPack encoder computes a block size from sample rate and channel count with an integer overflow, which can cause an infinite loop. A crafted audio file with a large declared sample rate and many channels can hang an application that transcodes it to WavPack.","audience":"developers","category":"package","nicknames":[],"who_cares":["ffmpeg","libavcodec","wavpack","audio-transcoding"],"confidence":0.6,"fix_status":"unknown","needs_auth":"no","worst_case":"Transcoding process hangs in an infinite loop, causing denial of service","analyst_note":"Confirm the fixed FFmpeg version and whether the patch link in NVD names it; the sources given do not state a fixed version.","how_to_check":"- Check whether your application or service uses FFmpeg (libavcodec) to encode WavPack audio.\n- Check the installed FFmpeg version with `ffmpeg -version`; the sources say the flaw affects versions through `9.0.2`.","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["no-wavpack-encoding","trusted-input-only"],"who_is_affected":"Applications that use FFmpeg's libavcodec to transcode audio into WavPack and accept untrusted input files are exposed to a hang. The sources describe a denial of service (infinite loop) rather than code execution. Systems that do not encode WavPack, or that only process trusted files, are less exposed.","user_interaction":"no","product_ecosystem":"","needs_special_setup":"yes","severity_if_unknown":"unknown"},"cost_usd":0.00076,"input_tokens":4633,"output_tokens":593,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-125234':14A,17A '-2026':13A,16A '9.0.2':73C 'applic':65B,122C 'attack':100C 'audio':19B,51B,105C 'audio-transcod':18B 'block':31B,92C 'caus':45B,86C 'channel':37B,61B,98C,119C 'comput':29B,91C 'contain':74C 'count':38B,99C 'craft':10A,50B,104C 'cve':12A,15A 'declar':56B,112C 'encod':6A,28B,81C 'ffmpeg':1A,21B,25B,71C 'file':52B,106C 'hang':7A,63B,121C 'header':111C 'huge':114C 'infinit':47B,88C 'init':82C 'integ':2A,41B,76C 'larg':55B 'libavcodec':22B 'libavcodec/wavpackenc.c':84C 'loop':48B,89C 'mani':60B,118C 'overflow':3A,42B,77C 'packag':23B 'rate':35B,58B,96C,116C 'sampl':34B,57B,95C,115C 'size':32B,93C 'suppli':102C 'transcod':8A,20B,67B,123C 'vulner':78C 'wav':11A,110C 'wavpack':5A,24B,27B,70B,80C,125C","nicknames":[],"mitigations":[],"who_affected":"Applications that use FFmpeg's libavcodec to transcode audio into WavPack and accept untrusted input files are exposed to a hang. The sources describe a denial of service (infinite loop) rather than code execution. Systems that do not encode WavPack, or that only process trusted files, are less exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"developers","plain_action":null,"pkeys":[],"ptokens":[],"labels":["audiotranscoding","ffmpeg","libavcodec","medium","package","wavpack"],"campaign_type":null,"search_a":"'-125234':14A,17A '-2026':13A,16A 'craft':10A 'cve':12A,15A 'encod':6A 'ffmpeg':1A 'hang':7A 'integ':2A 'overflow':3A 'transcod':8A 'wav':11A 'wavpack':5A","search_b":"'applic':65B 'audio':19B,51B 'audio-transcod':18B 'block':31B 'caus':45B 'channel':37B,61B 'comput':29B 'count':38B 'craft':50B 'declar':56B 'encod':28B 'ffmpeg':21B,25B 'file':52B 'hang':63B 'infinit':47B 'integ':41B 'larg':55B 'libavcodec':22B 'loop':48B 'mani':60B 'overflow':42B 'packag':23B 'rate':35B,58B 'sampl':34B,57B 'size':32B 'transcod':20B,67B 'wavpack':24B,27B,70B","search_c":"'9.0.2':73C 'applic':122C 'attack':100C 'audio':105C 'block':92C 'caus':86C 'channel':98C,119C 'comput':91C 'contain':74C 'count':99C 'craft':104C 'declar':112C 'encod':81C 'ffmpeg':71C 'file':106C 'hang':121C 'header':111C 'huge':114C 'infinit':88C 'init':82C 'integ':76C 'libavcodec/wavpackenc.c':84C 'loop':89C 'mani':118C 'overflow':77C 'rate':96C,116C 'sampl':95C,115C 'size':93C 'suppli':102C 'transcod':123C 'vulner':78C 'wav':110C 'wavpack':80C,125C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-09T19:17:01+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-2026-125234","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-125234","severity":null,"published_at":"2026-11-09T19:17:01+00:00","modified_at":"2026-11-09T19:17:01+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":109359,"url":"https://github.com/FFmpeg/FFmpeg/commit/e621da8ecdbef8edb8336cc899b962159dc2465c","title":"Patch: github.com","kind":"other","source":"nvd","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":109360,"url":"https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-wavpack-encoder-integer-overflow-infinite-loop-via-wavpack-encode-init","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"}