CVE-2026-74860: libxml2 Release of Invalid Pointer or Reference

Vulnerability summary

CVE-2026-74860 is a high (CVSS 8.5) Release of Invalid Pointer or Reference vulnerability in libxml2. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.5% of scored vulnerabilities.

Timeline

1. 08-09-2026
   PublishedVulnerability first disclosed.
2. 14-10-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in libxml2 with Python bindings enabled. A remote attacker could exploit this vulnerability by providing a specially crafted XML document containing a Document Type Definition (DTD) with enumerated attribute values. This triggers a double-free error in the SAX attributeDecl callback handler, where a string is freed twice. This flaw can lead to a denial of service (DoS) due to a reproducible crash in Python applications using the libxml2 SAX bindings.

• CWE-763Release of Invalid Pointer or ReferenceThe product attempts to return a memory resource to the system, but it calls the wrong release function or calls the appropriate release function incorrectly.