Bug 2506911 (CVE-2026-66037)

Summary: CVE-2026-66037 FFmpeg: FFmpeg: Denial of Service via uncontrolled resource consumption in IAMF demuxer
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: bbrownin
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in FFmpeg. An uncontrolled resource consumption vulnerability exists in the IAMF demuxer. An unauthenticated attacker can exploit this by supplying a specially crafted input file with a malicious count_label field. This can cause the system to allocate a large amount of memory, leading to resource exhaustion and a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-07-24 20:03:00 UTC 
FFmpeg through 8.1.2, fixed in commit 5d7112c, contains an uncontrolled resource consumption vulnerability in the IAMF demuxer that allows an unauthenticated attacker to cause multi-gigabyte memory allocation from a 17-byte input file by supplying a crafted count_label field. The mix_presentation_obu() function in libavformat/iamf_parse.c calls av_calloc(count_label, sizeof(*language_label)) with an attacker-controlled value before validating available OBU data, enabling an allocation amplification of approximately 126 million bytes per input byte that exhausts process memory or triggers an OOM-kill during format probing.