The remote host is missing a Mac OS X update that fixes a security issue.
The remote host is running a version of Mac OS X 10.4 that is older than version 10.4.6. Mac OS X 10.4.5 contains several security fixes for a local authentication bypass vulnerability. A malicious local user may exploit this vulnerability to bypass the firmware password and gain access to Single User mode.
Upgrade to version 10.4.6 or higher.