A bug in the Kerberos4 ftp client may cause heap overflow which leads to remote code execution

[Marcell Fodor <m.fodor () mail datanet hu>]

Kerberos4 ftp client is a simple ftp client, with the 
extensions defined by RFC 2228.
When authentication fails with AUTH, client will use 
USER/PASS command as other ones.

A bug in the code may cause a heap overflow which leads to 
remote code execution.
The overflow occurs when the server responds to client's 
request for passive mode. If the server
responds with a long reply in the place of IP and port, 
pasv buffer will overflow.

Affected version: 4-1.1.1

The real danger: an ftp server can simply modified to 
recognize Kerberos4 ftp client by it's protocol. You know 
the rest.

Details and exploit code: mantra.freeweb.hu

Marcell Fodor