High severity · published Aug 19, 2026
CVE-2026-75141
FFmpeg Heap Buffer Overflow in hvcC Box Writer via HEVC Muxing
7.8
CVSS
0.2%
EPSS
No
On KEV
Description
FFmpeg before commit acf5d7c contains a heap buffer overflow in the hvcC box writer. When writing an HEVC configuration record with more NAL units of a single type than the count field can represent, the NAL unit count overflows, causing a heap buffer overflow. A crafted HEVC input file triggers the overflow during muxing.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FF
FFmpeg · FFmpeg
before acf5d7cdc1f9ae8752c23e1ea8d7f355ed780781 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-75141
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-75141
code.ffmpeg.org
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/acf5d7cdc1f9ae8752c23e1ea8d7f355ed780781
code.ffmpeg.org
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24088
www.vulncheck.com
https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-in-hvcc-box-writer-via-hevc-muxing
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