Bug 2492243 (CVE-2026-58010)

Summary: CVE-2026-58010 glib: buffer over-read in glib/gvariant-serialiser.c via gvs_tuple_is_normal()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: kshier, rhel-process-autobot, stcannon, teagle, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in GLib. An off-by-one error can occur in the gvs_tuple_is_normal function in the glib/gvariant-serialiser.c file when doing an alignment padding check because the bounds check uses > instead of >=, causing an out-of-bounds read of only 1 byte. This issue can cause a minor information disclosure of 1 byte and a denial of service when the out-of-bounds read crosses a page boundary.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2494867, 2494868, 2494869    
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Description OSIDB Bzimport 2026-06-24 16:27:55 UTC 
gvs_tuple_is_normal() in glib/gvariant-serialiser.c:1253 has an off-by-one error in its alignment padding check. When checking whether padding bytes are zero, the bounds check uses > instead of >=, allowing a 1-byte out-of-bounds read when offset == value.size.