CVE-2026-64830

FFmpeg versions 2.1 through 8.1.2 contains a heap buffer overflow vulnerability in the VobSub subtitle demuxer that allows attackers to corrupt adjacent heap memory by supplying a malicious .sub/.idx subtitle file declaring more distinct stream IDs than the fixed-size array bounds in libavformat/mpeg.c. Attackers can craft a subtitle file with excessive distinct stream IDs to trigger unbounded writes beyond the vobsub->q[] array boundary via ff_subtitles_queue_insert(), potentially achieving arbitrary code execution in any application using FFmpeg's VobSub demuxer.

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/dbd495f066a85ba96b17433f4306582aa37c3951	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23657	Issue Tracking Patch
https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-via-vobsub-subtitle-demuxer	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*

History

28 Jul 2026, 17:00

Type	Values Removed	Values Added
References	~~() https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/dbd495f066a85ba96b17433f4306582aa37c3951 -~~	() https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/dbd495f066a85ba96b17433f4306582aa37c3951 - Patch
References	~~() https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23657 -~~	() https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23657 - Issue Tracking, Patch
References	~~() https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-via-vobsub-subtitle-demuxer -~~	() https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-via-vobsub-subtitle-demuxer - Third Party Advisory
First Time		Ffmpeg Ffmpeg ffmpeg
CPE		cpe:2.3:a:ffmpeg:ffmpeg::::::::

22 Jul 2026, 18:17

Type	Values Removed	Values Added
CWE	~~CWE-787~~	CWE-122

22 Jul 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-22 17:16

Updated : 2026-07-28 17:00

NVD link : CVE-2026-64830

Mitre link : CVE-2026-64830

CVE.ORG link : CVE-2026-64830

JSON object : View

Products Affected

ffmpeg

ffmpeg

CWE

CWE-122

Heap-based Buffer Overflow

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