CVE-2026-48981

Name of the Vulnerable Software and Affected Versions pam usb versions prior to 0.9.2

Description pam usb provides hardware authentication for Linux using removable media. The software calls the xmlReadFile() function with flags=0 when loading the configuration file, which allows libxml2 to process external entity references. This can lead to XML External Entity (XXE) processing, where the system may perform local file reads or make outbound network connections during XML parsing from the context of the authenticating process. Exploitation requires the configuration file to contain crafted XML entity references. Because the configuration file is owned by root, write access to the file is necessary for exploitation; however, the impact is significant as the pam usb.so module operates in setuid contexts such as sudo and su.

Recommendations Update to version 0.9.2.