"Basically if you pass a "-fusername" as an argument to the -l option you get full access to the OS as the user specified. In my example I do it as bin but it worked for regular users, just not for root. This combined with a reliable local privilege escalation exploit would be devastating. Expect mass scanning and possibly the widespread exploitation of this vulnerability.
Jeremy Kister writes "Errata Security reports about a bug found in the telnet daemon of Solaris 10. From the article: