CVE-2026-48066: pam_usb: Thread-unsafe static pointer in log.c causes data race under concurrent PAM authentication
pamusb 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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-48066?
The severity of CVE-2026-48066 is medium with a score of 5.7.
What type of vulnerability is CVE-2026-48066?
CVE-2026-48066 is classified as a race condition vulnerability in the pam_usb module.
How do I fix CVE-2026-48066?
To fix CVE-2026-48066, you should upgrade to pam_usb version 0.9.1 or later.
What software is affected by CVE-2026-48066?
The pam_usb software is affected by CVE-2026-48066.
What is the impact of CVE-2026-48066?
The impact of CVE-2026-48066 includes potential data races during concurrent PAM authentication processes.