CVE-2026-48983 — MEDIUM (5.8)

Vulnerability 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.

CVSS Score

5.8

MEDIUM

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

HIGH

Integrity

LOW

Availability

LOW

Related Weaknesses (CWE)

CWE-367

References

FAQ

What is CVE-2026-48983?

CVE-2026-48983 is a vulnerability with a CVSS score of 5.8 (MEDIUM). 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_us...

How severe is CVE-2026-48983?

CVE-2026-48983 has been rated MEDIUM with a CVSS base score of 5.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-48983?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.