CVE-2026-66039 | FFmpeg through 8.1.2, fixed in commit aafb5c6, contains a si… | CVSS 8.8 HIGH

Description

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.

Metadata

CVE ID: CVE-2026-66039
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-07-23 20:45 UTC
Published: 2026-07-24 19:42 UTC
Last updated: 2026-07-24 19:42 UTC
Primary CWE: CWE-190
Integer Overflow or Wraparound
Vendor / Product: FFmpeg / FFmpeg
Sources: cve.org · NVD

Severity & Metrics

8.8 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products (1)

Vendor	Product	Platform	Versions
FFmpeg	FFmpeg	—	0 ≤ 8.1.2, aafb5c655edc76a753275c383ebb139feb032718

Weakness (CWE)

CWE	Source	Description
CWE-122	cna	Heap-based Buffer Overflow
CWE-190	cna	Integer Overflow or Wraparound

CVSS scores (2)

Score	Severity	Version	Source	Vector
8.8	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.7	HIGH	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References (3)