MEDIUM · 5.8

CVE-2026-48982

pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open() without the O...

Vulnerability Description

pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open() without the O_EXCL flag. Without O_EXCL, the create operation is not atomic: two concurrent processes racing to update the same pad may both succeed in opening the file, with the second write silently overwriting the first. The one-time pad is the core replay-prevention mechanism of pam_usb. A successful race could result in the stored pad value diverging from what either process expected, potentially causing authentication failures or, in a precisely timed attack, creating a window for pad reuse. 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:L/I:H/A:L
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
LOW

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-48982?

CVE-2026-48982 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, when updating a one-time pad file, a temporary file is created using open() without the O...

How severe is CVE-2026-48982?

CVE-2026-48982 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-2026-48982?

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