CVE-2026-48983
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
18/06/2026
Last modified:
22/06/2026
Description
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.
Impact
Base Score 3.x
5.80
Severity 3.x
MEDIUM