Red Hat Bugzilla – Bug 57589
running up2date breaks ftp
Last modified: 2007-04-18 12:38:45 EDT
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2.1) Gecko/20010901 Description of problem: After running up2date under RH 7.2 ftp no longer works. I get "invalid login" every time I try, yet I can login using telnet. Version-Release number of selected component (if applicable): How reproducible: Always Steps to Reproduce: 1.Run up2date under RH 7.2 2.Run ftp localhost 3.Try to login using your username/password Actual Results: Login failed Expected Results: Login successful Additional info: up2date can be hazardous to RH Linux
Turns out I installed the PD Korn shell in /bin/ksh, but did not put this into /etc/shells. This caused wu-ftpd to return "invalid login" for any user who selected this as his/hre default shell. This is a bug in wu-ftpd: it should say "unknown shell" or something more helpful than "invalid login".
No, it's not a bug in wu-ftpd. It's a security feature. If a cracker is told why he can't log in as a specific user, he'll have a much better chance at circumventing it ("oh, this user must exist!").