{"id":"CVE-2026-76641","title":"Expat through 2.8.3 contains an out-of-bounds read vulnerability that allows attackers to trigger memory corruption by processing XML with external entity parsers created via XML_ExternalEntityParserCreate","summary":"Expat through 2.8.3 contains an out-of-bounds read vulnerability that allows attackers to trigger memory corruption by processing XML with external entity parsers created via XML_ExternalEntityParserCreate. A struct size mismatch between…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-125"],"published":"2026-08-20","updated":"2026-09-24","sourceUpdated":"2026-09-24T20:02:50.260","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-76641","references":[{"url":"https://github.com/libexpat/libexpat/commit/98599f6dcc2b460410881fe420f5f55d6bec63bf","label":"disclosure@vulncheck.com"},{"url":"https://github.com/libexpat/libexpat/pull/1331","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/expat-out-of-bounds-read-via-dtdcopy","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-76641.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-76641"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2520649"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-76641"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-76641"},{"url":"https://access.redhat.com/errata/RHSA-2026:65568"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00609,"epssPercentile":0.4686,"ingestedAt":"2026-09-24T20:51:40.212Z","vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4","hardened_images"],"patched":["hardened_images"],"slug":"CVE-2026-76641","body":"## Overview\n\nExpat through 2.8.3 contains an out-of-bounds read vulnerability that allows attackers to trigger memory corruption by processing XML with external entity parsers created via XML_ExternalEntityParserCreate. A struct size mismatch between ELEMENT_TYPE members causes storeAtts to read the attIndex member past allocated memory boundaries, resulting in failure to normalize whitespace in non-CDATA attributes or a wild pointer dereference causing a segfault. This vulnerability was introduced by the fix for CVE-2026-66046.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:65568** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65568)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-76641.json)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}