CVE-2026-66040

HIGH CVSS 4.0: 8.7 EPSS 0.55%
Updated Jul 27, 2026
Payload
Parameter Value
CVSS 8.7 (HIGH)
Type CWE-122 (Heap-based Buffer Overflow)
Vendor Payload
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Vulnerable Products

ffmpeg:ffmpeg