Bug 2539442 (CVE-2026-96611)

Summary: CVE-2026-96611 ffmpeg: FFmpeg: Data corruption and information disclosure via signed integer overflow in HEIF processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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. A local attacker can craft a malicious High Efficiency Image File Format (HEIF) file that, when processed, can cause a signed integer overflow. This overflow allows width and height values to become negative, bypassing internal validity checks. This can lead to data corruption and potentially information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2540646, 2540647, 2540649, 2540650, 2540648    
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Description OSIDB Bzimport 2026-09-23 14:38:06 UTC 
FFmpeg before 9.0 has a signed integer overflow in libavformat/mov.c. In mov_read_ispe(), uint32_t width/height values from a crafted HEIF ispe box are stored into signed int fields without bounds checking, allowing values exceeding INT_MAX to become negative. In read_image_grid(), accumulating these values causes signed integer overflow (undefined behavior per C17 section 6.5), which on x86 wraps to a small positive value, bypassing downstream validity checks.