Description
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, src/device.c passed the return values of udisks_drive_get_serial(), udisks_drive_get_vendor(), and udisks_drive_get_model() directly to strcmp() without NULL checks. The GIO/UDisks API documentation states these accessors can return NULL for devices that do not expose the corresponding field. Passing NULL to strcmp() is undefined behaviour (typically a SIGSEGV). This vulnerability is fixed in 0.8.7.
References1
Metrics
- CVSS 3.1
-
4.6
MEDIUM
Score source: CNA
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 15 November 2026
- CWE
- CWE-476
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.