CVE-2026-48983
MEDIUM
MEDIUM
Priority: 0.01
BB Relevance:
27/100
Published: 2026-06-18
Modified: 2026-10-26
First seen: 2026-10-29
Status: active
Attack Surface
No Interaction
Conf. Impact
CVSS Vector Breakdown
AV:
Local
AC:
High
PR:
Low
UI:
None
S:
Unchanged
C:
High
I:
Low
A:
Low
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.