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CVE-2026-76641 is an out-of-bounds read in Expat/libexpat through version 2.8.3. When XML is processed using an external-entity parser created with XML_ExternalEntityParserCreate, a size mismatch between ELEMENT_TYPE structures can cause storeAtts() to read the attIndex member beyond the allocated object boundary. The flaw was introduced by the fix for CVE-2026-66046. The invalid read can prevent whitespace normalization for non-CDATA attributes or yield a wild pointer dereference and process crash.
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An out-of-bounds read and memory-corruption vulnerability in Expat through version 2.8.3. Processing specially crafted XML using external entity parsers can cause an out-of-bounds attIndex read, leading to whitespace-normalization failure or a wild-pointer dereference and segmentation fault. The flaw was introduced by the fix for CVE-2026-66046.
An Expat out-of-bounds read caused by an ELEMENT_TYPE structure-size mismatch in external-entity parsers. It can cause incorrect attribute whitespace normalization or a wild-pointer dereference and segmentation fault. The content states it was introduced by the fix for CVE-2026-66046.
A denial-of-service oriented vulnerability tracked as CVE-2026-76641, reflected by CVSS vectors indicating network attackability and high availability impact. The content does not describe the root cause, but it identifies Ubuntu-related affected packages and marks the issue as unpatched.
An out-of-bounds read vulnerability in libexpat/Expat through version 2.8.3 that can lead to memory corruption or a segfault when processing XML with external entity parsers created via XML_ExternalEntityParserCreate.
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Cross-references every affected SKU, including bundled OEM variants.
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