Ubuntu Security Notices guidance
Vendor revision: Sep 9, 2026USN-8716-1 fixed several vulnerabilities in FFmpeg.
Vulnerability intelligence
CVE-2026-75143 and is rated Critical severity with a CVSS score of 9.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
USN-8716-1 fixed several vulnerabilities in FFmpeg.
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.
Source: NVD