Bug 2526159

Summary: CVE-2026-75143 ffmpeg: FFmpeg Heap Buffer Overflow via RIST Protocol Reader [fedora-all]
Product: [Fedora] Fedora Reporter: Thibault Guittet <tguittet>
Component: ffmpegAssignee: Multimedia SIG <multimedia-sig>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: asn, dominik, multimedia-sig, ngompa13, philip.wyett
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["af4e7a75-abc0-4a9e-af98-a6c61c1d72d2"]}
Fixed In Version: Doc Type: ---
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Documentation: --- CRM:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2519758    

Description Thibault Guittet 2026-08-31 08:12:15 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.