CVE-2026-65704

FFmpeg through 8.1.2 contains an out-of-bounds write vulnerability that allows attackers to cause heap corruption by supplying a crafted ffconcat file processed with the -safe 0 flag. The TY demuxer's demux_audio() function decrements packet size without bounds checking, producing a negative size value that is passed to memcpy() in shorten_decode_frame(), where conversion to size_t wraps the value to near SIZE_MAX and triggers reads beyond the source allocation and writes far beyond the Shorten decoder's bitstream buffer.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/de771bd52774a52d45b0e2c82e56995a1ef40df7	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23767	Issue Tracking Patch
https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-write-via-ty-demuxer-and-shorten-decoder	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-23 20:17

Updated : 2026-08-07 00:16

NVD link : CVE-2026-65704

Mitre link : CVE-2026-65704

CVE.ORG link : CVE-2026-65704

JSON object : View

Products Affected

ffmpeg

ffmpeg

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

CWE-787

Out-of-bounds Write

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