can someone please try this qmail exploit?

Georgi Guninski guninski at
Tue May 17 03:32:13 PDT 2005

can some please try a qmail-smtpd remote exploit on freebsd 5.4 amd64?

what is needed:
- freebsd 5.4 amd64
- 13GB virtual memory - ram + swap (probably less will do, not quite sure)
- vanilla djb qmail - (an easy way to
  install it is to install qmail from ports, then change in
conf-groups "nofiles" to "qnofiles" and build and install vanilla
qmail. vanilla qmail is important.

how to reproduce:

donwload the perl proggie:


start it on localhost.

attach a gdb to qmail-smtpd and wait.

if you get:
Program received signal SIGTRAP, Trace/breakpoint trap.
0x000000000050cbac in ?? ()
(gdb) x/i $rip
0x50cbac:       int3   

then the exploit works.

a lot of memory is used, so a production machine may be lagged.
on an athlon64 2800+ with 1.5G ram the exploit takes about 1 hour.
it was reported that with 8G ram the exploit takes about 10 minutes.
there are flames on the qmail mailing list if this is a bug or not.



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