Bug 2491184 (CVE-2026-56407)

Summary: CVE-2026-56407 libexpat: libexpat: Arbitrary code execution due to integer overflow
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: akhatavk, aos-team-art-private, asdas, dpaolell, gotiwari, jdelft, jhorak, jupierce, lgarciaa, mbiarnes, mvyas, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
An integer overflow exists in libexpat's doProlog function due to improper handling of entity value lengths. A local attacker could exploit this to execute arbitrary code or access sensitive system data.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2508371, 2508372    
Bug Blocks:    

Description OSIDB Bzimport 2026-06-21 16:01:20 UTC
libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.