Bug 2565054

Summary: CVE-2026-120246 chromium: ffmpeg: Information disclosure via uninitialized palette entries in CDXL decoder [epel-8]
Product: [Fedora] Fedora EPEL Reporter: Marian Rehak <mrehak>
Component: chromiumAssignee: Than Ngo <than>
Status: CLOSED WONTFIX QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: epel8CC: go-sig, pigpigman8686, spotrh, suraj.ghimire7, than, yaneti
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e07bc702-1bed-4127-abca-3f4638799726"]}
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Clone Of: Environment:
Last Closed: 2026-11-03 12:37:14 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2564498    

Description Marian Rehak 2026-11-02 10:33:26 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.

FFmpeg 4.4 through 9.0.2 contains a use of uninitialized variable vulnerability in the CDXL decoder that leaks stack memory into decoded pixels via unfilled HAM palette entries. Attackers can craft a type-0 CDXL file whose HAM pixels select unfilled new_palette entries in cdxl_decode_ham8() or cdxl_decode_ham6(), exposing stack bytes and pointer fragments in the BGR24 output.
Comment 1 Than Ngo 2026-11-03 12:37:14 UTC 
Closing it as WONTFIX as i stopped updating chromium in EPEL8 because it started to require newer C++ standard that the aging system didn't support