CVE-2026-66039 PUBLISHED

FFmpeg MACE6 Audio Decoder Heap Out-of-Bounds Write via CAF File

Assigner: VulnCheck
Reserved: 23.07.2026 Published: 24.07.2026 Updated: 24.07.2026

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.

Metrics

CVSS Vector: 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
CVSS Score: 8.7

Product Status

Vendor FFmpeg
Product FFmpeg
Versions Default: affected
  • affected from 0 to 8.1.2 (incl.)
  • Version aafb5c655edc76a753275c383ebb139feb032718 is unaffected

Credits

  • Adrian Junge (vurlo) finder

References

Problem Types

  • Integer Overflow or Wraparound CWE
  • Heap-based Buffer Overflow CWE