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...