CVE-2026-48983: Mcdope Pam USB

Medium severity, CVSS 5.8. EPSS: 0.1% chance of exploitation in the next 30 days.

pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, a symlink race condition exists in per-device and per-user pad directory creation. pam_usb uses a check-then-act pattern: it calls lstat() to test for existence and then calls mkdir() separately to create the directory. A local attacker can win the race between these calls by replacing the target path with a symlink to a directory they control. If successful, one-time pad files may be written to an attacker-controlled location, potentially exposing future pad values before use or disrupting authentication. This issue has been fixed in version 0.9.2.

Affected products

• Mcdope Pam USB: before 0.9.2 (fixed in 0.9.2)

Published 2026-06-18. Last modified 2026-06-22.