CVE-2026-75143
CriticalCVSS 9.8Summary
FFmpeg before commit 1c10bcc contains a heap buffer overflow in the RIST protocol reader (libavformat/librist.c). The librist_read() function ignores its size argument and copies 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.
Risk Assessment
A remote attacker sending RIST packets can trigger a buffer overflow, potentially leading to crashes or arbitrary code execution.
Recommendation
Update FFmpeg to a version containing the fix (commit 1c10bcc or later) and restrict access to services using RIST.
Original NVD description (English source)
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.