The libexpat project's xmlwf tool versions prior to 2.8.2 contain an integer overflow vulnerability in the endDoctypeDecl function triggered by NOTATION declarations. This integer overflow (CWE-190) may allow an attacker to cause memory corruption, potentially impacting confidentiality and integrity of the system processing XML data. The vulnerability has a CVSS 3.1 base score of 6.9, with attack vector local, high attack complexity, no privileges required, no user interaction, and unchanged scope.

Successful exploitation of this integer overflow could lead to unauthorized disclosure or modification of data (high confidentiality and integrity impact) and limited disruption of service (low availability impact). The vulnerability requires local access and has high attack complexity, reducing the likelihood of exploitation. No known exploits are reported in the wild.

A fix is available in libexpat version 2.8.2 and later. Users and administrators should upgrade to version 2.8.2 or newer to remediate this vulnerability. Since no official vendor advisory or patch link is provided, verify the upgrade from the official libexpat project sources. Patch status is not yet confirmed in vendor advisories; check the vendor advisory for current remediation guidance.