Bug 2490668 (CVE-2026-56131)

Summary: CVE-2026-56131 libexpat: libexpat: Use-after-free vulnerability due to insufficient handler call depth tracking
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: gotiwari, jhorak, mvyas, rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A use-after-free vulnerability in libexpat occurs because handler call depth isn't properly tracked when XML_ResumeParser is invoked during policy violations. This flaw can lead to information disclosure, data corruption, or denial of service.
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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: 2509709, 2509708    
Bug Blocks:    

Description OSIDB Bzimport 2026-06-19 05:01:24 UTC
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).