Re: pop3

[Rafal Kupka <kupson@polsl.gliwice.pl>]

On Sun, Jul 29, 2001 at 04:44:57PM -0700, Rob Hudson wrote:
Hello,

[cut - about secure pop3 daemon]
> 
> I currently have fetchmail opening up a SSH tunnel, and get my mail
> via popa3d.  I'll attach relavent scripts...
> 
> /home/user/.fetchmailrc:
> -----------------------
> poll cogit8.org via localhost protocol pop3 port 12574:
>   preconnect "ssh -C -f -L 12574:cogit8.org:110 cogit8.org sleep 10"
>   password <your_password>;
> 
> I guess that's it.  This basically says, 
> 
> preconnect (do this before fetching mail) 
> open a SSH channel from server cogit8.org port 110 to localhost port
> 12574 (arbitrary port number), wait 10 seconds for fetchmail to get in
> there.
> 
> then,
> fetchmail on localhost port 12574.  
This is unsecure - any localhost user can sniff your passwords.
---
kupson@temp: ~$ nc -l -p 60001 # choosen port number
+OK
USER kupson

PASS <mypassword>

QUIT

kupson@temp: ~$
---
Type "+OK" after fetchmail connects to netcat, then several times <ENTER> .

Ssh didn't notify fetchmail that it cannot forwand
remote port to localhost.

You can run fetchmail as user root and choose port number < 1024,
but it's even worse security problem.

Somebody know how do it better ?

[cut - rest] 

Kupson
PS: Sorry for my english.
-- 
Great software without the knowledge to run it is pretty useless.
(Linux Gazette #1)