Libav: FFmpeg through 8.1.2, fixed in commit aafb5c6, contains a signed integer overflow vulnerability in the MACE6 audio decoder that allows attackers to… (CVE-2026-66039)
FFmpeg versions through 8.1.2 contain a signed integer overflow vulnerability in the MACE6 audio decoder. This flaw allows attackers to craft a malicious CAF audio file with specially manipulated bytes_per_packet and frames_per_packet values, triggering an integer overflow during output sample count computation. The overflow leads to an undersized buffer allocation and a heap out-of-bounds write, potentially enabling arbitrary code execution. The vulnerability is fixed in a commit identified as aafb5c6.
AI Analysis
Technical Summary
A signed integer overflow vulnerability exists in the MACE6 audio decoder of FFmpeg through version 8.1.2. Attackers can supply a crafted CAF file with oversized bytes_per_packet and frames_per_packet values in the desc chunk, causing an integer overflow in the mace_decode_frame() function during output sample count calculation. This results in an undersized buffer allocation and a heap out-of-bounds write, which could allow attackers to corrupt heap memory and potentially execute arbitrary code. The issue is addressed in commit aafb5c6.
Potential Impact
Successful exploitation can lead to heap memory corruption via a heap out-of-bounds write, which may enable arbitrary code execution. The vulnerability affects confidentiality, integrity, and availability of affected systems.
Mitigation Recommendations
A fix for this vulnerability is available and was introduced in commit aafb5c6. Users should update FFmpeg to a version that includes this commit or later. Since this is not a cloud service, remediation requires applying the patch or upgrading the affected software. Patch status is confirmed fixed in the referenced commit.
Libav: FFmpeg through 8.1.2, fixed in commit aafb5c6, contains a signed integer overflow vulnerability in the MACE6 audio decoder that allows attackers to… (CVE-2026-66039)
Description
FFmpeg versions through 8.1.2 contain a signed integer overflow vulnerability in the MACE6 audio decoder. This flaw allows attackers to craft a malicious CAF audio file with specially manipulated bytes_per_packet and frames_per_packet values, triggering an integer overflow during output sample count computation. The overflow leads to an undersized buffer allocation and a heap out-of-bounds write, potentially enabling arbitrary code execution. The vulnerability is fixed in a commit identified as aafb5c6.
CVSS v3.1
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
A signed integer overflow vulnerability exists in the MACE6 audio decoder of FFmpeg through version 8.1.2. Attackers can supply a crafted CAF file with oversized bytes_per_packet and frames_per_packet values in the desc chunk, causing an integer overflow in the mace_decode_frame() function during output sample count calculation. This results in an undersized buffer allocation and a heap out-of-bounds write, which could allow attackers to corrupt heap memory and potentially execute arbitrary code. The issue is addressed in commit aafb5c6.
Potential Impact
Successful exploitation can lead to heap memory corruption via a heap out-of-bounds write, which may enable arbitrary code execution. The vulnerability affects confidentiality, integrity, and availability of affected systems.
Mitigation Recommendations
A fix for this vulnerability is available and was introduced in commit aafb5c6. Users should update FFmpeg to a version that includes this commit or later. Since this is not a cloud service, remediation requires applying the patch or upgrading the affected software. Patch status is confirmed fixed in the referenced commit.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-84qc-6h9r-4w33
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-66039"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a6542289c2644c7f808a029
Added to database: 07/25/2026, 23:09:28 UTC
Last enriched: 08/08/2026, 16:58:03 UTC
Last updated: 09/07/2026, 22:52:14 UTC
Views: 109
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