CVE-2026-66039CWE-122CWE-190

CVE-2026-66039

High · published July 25, 2026

CVSS v3.1
8.8
EPSS
0%
Percentile
22.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00307 · 22.3th percentile
Weaknesses
CWE-122 · Heap-based Buffer Overflow; CWE-190 · Integer Overflow or Wraparound
Published
2026-07-25T00:18Z
Affected products (1)
ProductVersionsFixed in
ffmpeg/ffmpeg≤ 8.1.2—
References (3)
EPSS history
Timeline
  • 24 JUL 19:42Z
    FFmpeg MACE6 Audio Decoder Heap Out-of-Bounds Write via CAF File
    cvelistv5