Bug 2513021 (CVE-2026-72522)

Summary: CVE-2026-72522 expat: libexpat: Denial of Service due to incorrect Unicode surrogate handling
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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A flaw in libexpat's _toUtf16 functions mishandles Unicode low surrogates by treating them as high surrogates. An attacker can exploit the resulting out-of-bounds read to trigger an infinite loop, causing a denial of service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2513993    
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Description OSIDB Bzimport 2026-08-10 03:51:13 UTC
libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the *_toUtf16 functions.