CVE-2026-66039

FFmpeg through 8.1.2, fixed in commit aafb5c6, contains a signed integer overflow vulnerability in the MACE6 audio decoder that allows attackers to corrupt heap memory by supplying a crafted CAF file with a malicious bytes_per_packet value. Attackers can craft a CAF file with oversized bytes_per_packet and frames_per_packet values in the desc chunk to trigger an integer overflow in mace_decode_frame() during output sample count computation, resulting in an undersized buffer allocation and heap out-of-bounds write that could enable code execution.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

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/aafb5c655edc76a753275c383ebb139feb032718	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23631	Issue Tracking Patch
https://www.vulncheck.com/advisories/ffmpeg-mace6-audio-decoder-heap-out-of-bounds-write-via-caf-file	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-24 20:18

Updated : 2026-08-07 00:46

NVD link : CVE-2026-66039

Mitre link : CVE-2026-66039

CVE.ORG link : CVE-2026-66039

JSON object : View

Products Affected

ffmpeg

ffmpeg

CWE

CWE-122

Heap-based Buffer Overflow

CWE-190

Integer Overflow or Wraparound

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