Bug 2433348 (CVE-2026-1489)

Summary: CVE-2026-1489 Glib: GLib: Memory corruption via integer overflow in Unicode case conversion
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: adudiak, kshier, stcannon, teagle, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in GLib. An integer overflow vulnerability in its Unicode case conversion implementation can lead to memory corruption. By processing specially crafted and extremely large Unicode strings, an attacker could trigger an undersized memory allocation, resulting in out-of-bounds writes. This could cause applications utilizing GLib for string conversion to crash or become unstable.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2433350, 2433351, 2433352, 2433353, 2433354, 2433355, 2433356, 2433357, 2433358, 2433359, 2433360, 2433362, 2433363, 2433364, 2433365, 2433366, 2433367, 2433368, 2433369, 2433370    
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Description OSIDB Bzimport 2026-01-27 14:03:29 UTC 
Integer Overflow vulnerability in GLib’s Unicode case conversion implementation. The flaw is caused by mixing signed and unsigned integer types when calculating output buffer lengths across output_marks() and real_tolower(). An integer overflow can result in an undersized heap allocation followed by out-of-bounds writes during UTF-8 character conversion. Exploitation requires an application to process attacker-controlled large Unicode input and may result in crashes or potential memory corruption.