CVE-2026-48985 pam_usb: NULL Dereference Crash in pusb_is_loginctl_local when loginctl Returns Empty Remote Field

pamusb provides hardware authentication for Linux using ordinary removable media. In versions 0.9.1 and below, pusbisloginctllocal can cause a NULL dereference crash when parsing loginctl output. The function calls popen and reads the result; if the Remote field is only a newline, fgets succeeds...