Description
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.1, src/log.c contains a process-wide static pointer that is written on every PAM invocation with the address of a stack-local variable. This violates the PAM re-entrancy requirement and creates a data race when the PAM stack is invoked concurrently from multiple threads. This vulnerability is fixed in 0.9.1.
References3
Metrics
- CVSS 3.1
-
5.7
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 15 November 2026
- CWE
- CWE-362CWE-476
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