Bug 2506935 (CVE-2026-66041)

Summary: CVE-2026-66041 ffmpeg: FFmpeg: Arbitrary code execution via crafted PGS/SUP subtitle file
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
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's `vf_quirc` filter, which handles subtitle processing. A remote attacker can exploit this heap out-of-bounds write vulnerability by providing a specially crafted PGS/SUP subtitle file. This file, with mismatched frame dimensions, can cause the software to write data beyond the allocated memory buffer. Successful exploitation can lead to heap corruption, a process crash, and potentially arbitrary code execution, allowing the attacker to run malicious code on the affected system.
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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: 2510584, 2510586, 2510588, 2510597, 2510598    
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Description OSIDB Bzimport 2026-07-24 21:01:26 UTC 
FFmpeg 7.0 through 8.1.2, fixed in commit 4da9812, contains a heap out-of-bounds write vulnerability in the vf_quirc filter that allows an attacker to corrupt heap memory by supplying a crafted PGS/SUP subtitle file with mismatched frame dimensions. Attackers can provide a subtitle file whose second presentation has larger dimensions than its first, causing av_image_copy_plane() to copy data exceeding the initial allocation size into the undersized libquirc grayscale image buffer, resulting in heap corruption and process crash with potential for code execution.