Bug 2565164

Summary: CVE-2026-120252 python-imagecodecs: imagecodecs: Denial of Service via stack-based buffer overflow in lossless JPEG parser [fedora-43]
Product: [Fedora] Fedora Reporter: Oleg Sushchenko <osushche>
Component: python-imagecodecsAssignee: Orion Poplawski <orion>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 43CC: orion
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["a75b15c0-8758-4638-a11a-e96bdde1a1a9"]}
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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:    
Bug Blocks: 2564504    

Description Oleg Sushchenko 2026-11-02 13:11:29 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.

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.