CVE-2026-75146

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 17:21

Updated : 2026-08-31 20:37

NVD link : CVE-2026-75146

Mitre link : CVE-2026-75146

CVE.ORG link : CVE-2026-75146

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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