Bug 2540477 (CVE-2026-93542)

Summary: CVE-2026-93542 libXi: libXi: Denial of Service via out-of-bounds read during XI2 class parsing
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: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in libXi. An out-of-bounds read vulnerability occurs during the parsing of X Input Extension (XI2) device class data. A malicious X server can exploit this vulnerability by sending specially crafted class responses to a connected client application. This causes the client to read beyond memory boundaries and crash, resulting in a Denial of Service (DoS).
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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: 2540633    
Bug Blocks:    

Description OSIDB Bzimport 2026-09-24 16:58:44 UTC
An out-of-bounds read in libXi's XI2 class parsing via size_classes() and copy_classes() in libXi before 1.8.4 could be used by malicous servers to crash the X client.