CVE-2026-66040

FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary 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/b506fafec9a19fcbc2be5271875fd4a63d6615bc
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23786
https://www.vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-via-png-apng-exif-encoder

Configurations

No configuration.

History

24 Jul 2026, 20:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-24 20:18

Updated : 2026-07-29 05:17

NVD link : CVE-2026-66040

Mitre link : CVE-2026-66040

CVE.ORG link : CVE-2026-66040

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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