Bug 2564504 (CVE-2026-120252)

Summary: CVE-2026-120252 imagecodecs: imagecodecs: Denial of Service via stack-based buffer overflow in lossless JPEG parser
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: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in imagecodecs. A stack-based buffer overflow exists in the lossless JPEG parser within the decode_jpegsof3() function due to improper validation of Huffman table symbol counts. By enticing a user or application to process a specially crafted lossless JPEG image file, an attacker could trigger stack memory corruption, causing the application to crash and resulting in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2565164, 2565165, 2565167    
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Description OSIDB Bzimport 2026-11-01 01:02:41 UTC
imagecodecs 2023.1.23 through 2026.10.10 contains a stack-based buffer overflow vulnerability in the lossless JPEG Define Huffman Table parser in decode_jpegsof3(). Attackers can supply a crafted lossless JPEG whose DHT symbol counts wrap an 8-bit sum, overflowing the 32-entry HufVal and HufSz stack arrays and crashing the calling process.