CVE-2026-75143

FFmpeg before commit 1c10bcc contains a heap buffer overflow in the RIST protocol reader (libavformat/librist.c). librist_read() ignored its size argument and copied the full received payload length into the caller-provided destination buffer, overflowing it when the payload exceeds the destination size. This is reachable via the async:rist:// URL scheme, where the async wrapper supplies a smaller buffer than the received payload. A remote RIST sender can trigger the overflow by sending a packet whose payload exceeds the caller buffer size.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/1c10bcc2e17255dacb717a25ab3db142ce390602
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24089
https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-via-rist-protocol-reader

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 17:21

Updated : 2026-08-31 20:37

NVD link : CVE-2026-75143

Mitre link : CVE-2026-75143

CVE.ORG link : CVE-2026-75143

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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