CVE-2026-75146

HIGH 8.1

FFmpeg Out-of-Bounds Read in DASH Demuxer via dashdec.c

CVSS Score

8.1

EPSS Score

0.0%

EPSS Percentile

0th

FFmpeg before commit 65b0dab contains an out-of-bounds read in the DASH demuxer (libavformat/dashdec.c). When a live DASH manifest is refreshed with a startNumber that is lower than the previous value, the current sequence number is driven negative. The fragment retrieval function checked only the upper bound before indexing the fragments array, allowing a negative index to be used and causing an out-of-bounds read. A malicious or misconfigured DASH server can trigger this by serving a live manifest with a decreasing startNumber across a manifest refresh.

CWE	CWE-125
Vendor	ffmpeg
Product	ffmpeg
Published	Aug 19, 2026

Stay Ahead of the Next One

Get instant alerts for ffmpeg ffmpeg

Be the first to know when new high vulnerabilities affecting ffmpeg ffmpeg are published — delivered to Slack, Telegram or Discord.

Get Free Alerts → Free · No credit card · 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Affected Versions

FFmpeg / FFmpeg

0 < 65b0dab903e5975e036b30ecc58f5935d4f151e0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

code.ffmpeg.org: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24093 code.ffmpeg.org: https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/65b0dab903e5975e036b30ecc58f5935d4f151e0 vulncheck.com: https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-read-in-dash-demuxer-via-dashdec-c

Credits

Joshua Rogers (AISLE Research)