CVE-2026-48981

pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, pam_usb calls xmlReadFile() with flags=0 when loading the configuration file, allowing libxml2 to process external entity references (XXE), potentially making outbound network connections or local file reads at XML parse time from the context of the authenticating process. The vulnerability requires the configuration file to contain crafted XML entity references. Since pam_usb.conf is root-owned, direct exploitation requires prior write access to the config, but the defence-in-depth impact is significant given that pam_usb.so runs in setuid contexts (sudo, su). This issue has been fixed in version 0.9.2.
Configurations

No configuration.

History

18 Jun 2026, 20:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-06-18 20:16

Updated : 2026-06-18 20:16


NVD link : CVE-2026-48981

Mitre link : CVE-2026-48981

CVE.ORG link : CVE-2026-48981


JSON object : View

Products Affected

No product.

CWE
CWE-611

Improper Restriction of XML External Entity Reference