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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-66040 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 8.7 HIGH
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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/b506fafec9a19fcbc2be5271875fd4a63d6615bc VulnCheck
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23786 VulnCheck
https://www.vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-via-png-apng-exif-encoder VulnCheck

Weakness Enumeration

CWE-ID CWE Name Source
CWE-122 Heap-based Buffer Overflow VulnCheck  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-66040
NVD Published Date:
07/24/2026
NVD Last Modified:
07/24/2026
Source:
VulnCheck