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Old 06-27-2003
Khayman
 
Posts: n/a
Default Re: I got hacked 3 times

"roman dissertori" <r.dissertori@ecom-it.at> wrote in
news:bdhd01$d95$1@ulysses.news.tiscali.de:

> Ok, thank you very much everyone!
> These advices are very useful to me
> - I'll always look for updates for this linux-distribution
> - Scanning my ports for any security holes from outside.


Sounds like a good start!
Good sites for scanning from the outside is grc.com (a little windows-
aimed and hyped, but still) and pcflank.com.
Nmap is a very good (and free) tool you can use for this as well.

> ps:
> He/She cracked (thanks for teaching me the difference) my Computer
> trough an open Port, I don't know which one.



Well, it's not that the port was open, it's more that you had some
service sitting there unupdated!
Number one security tip: Make sure that the services you are running are
needed - running RPC/portmap/etc with no reason is not just unneccessary,
it's also quite dangerous!

Take a look at "netstat -tupan" - it will show which services are
listening to the internet, if nothing is listening then nothing can be
"hacked", atleast not remotely.


> I noticed that hacker because he/she made _one_ mistake: He/She forgot
> to delete the data in the /tmp folder where I found his evil scripts
> that he/she executed -> One Script for example was for moving the
> logfiles into /dev/null and lots of other stuff.


Remember that once people run a so called "rootkit", or "hack" your linux
system, it's not your system anymore!
Any command can be lying to you - "ps"/"pstree" can be hiding evil
programs, "ls" can be hiding directories from you - if you know what to
do and how to clean up the mess they did, ok no need to re-install.
If you don't then please re-install your server and try better the next
time!

> Sorry I don't use ipchains. I wrote it I know, but that was wrong ->
> I'm using iptables.
> I don't know much about the difference, but iptables is newer, right?
> (and I guess better)


Ah well.. ipchains is older, came with the 2.2 series of kernel -
iptables is newer and better. They both lack the most important component
needed to create a near perfect firewall - a good administrator.
That's where you has to come in!

Good luck!

Khay.
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