COMMAND
procmail
SYSTEMS AFFECTED
Linux Slackware 3.5 (others?)
PROBLEM
M.C.Mar posted following. He found buffer overflow in procmail.
woozle:~> gdb ./procmail
[...]
(gdb) r `perl -e 'print "A" x 5000'`
Starting program: /home/emsi/./procmail `perl -e 'print "A" x 5000'`
[You need to type ^D here!!!]
procmail: Couldn't create "/var/spool/mail/emsi"
(no debugging symbols found)...(no debugging symbols found)...
Program received signal SIGSEGV, Segmentation fault.
0x4008a107 in malloc ()
Interesting, isn't it? But look at this:
(gdb) r `perl -e 'print "A" x 7000'`
[...]
Starting program: /home/emsi/./procmail `perl -e 'print "A" x 7000'`
procmail: Couldn't create "/var/spool/mail/emsi"
Program received signal SIGSEGV, Segmentation fault.
0x4007dfa3 in strncmp ()
But this time, there is something more interesting:
(gdb) x/i 0x4007dfa3
0x4007dfa3 <strncmp+19>: lodsb %ds:(%esi),%al
(gdb) info registers
eax 0x41414141 1094795585
esi 0x41414141 1094795585
ds 0x2b 43
Procmail in question is procmail v3.10 1994/10/31 which comes with
Slackware 3.5.
SOLUTION
Nothing yet, but still to be sure remove suid and watch out for
updates.