Bug 2519758 (CVE-2026-75143)

Summary: CVE-2026-75143 ffmpeg: FFmpeg Heap Buffer Overflow via RIST Protocol Reader
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: bbrownin, gtanzill, jbuscemi
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in FFmpeg. A heap buffer overflow in the RIST protocol reader allows a remote attacker to trigger memory corruption by sending an oversized packet to an FFmpeg instance receiving a RIST stream. The librist_read() function ignores its buffer size argument, copying the full payload into the caller-provided buffer without bounds checking. This could lead to denial of service or arbitrary code execution.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2526158, 2526159    
Bug Blocks:    

Description OSIDB Bzimport 2026-08-19 16:53:18 UTC 
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.