Re: Blocking Port scans

From: Ivan . (ivanhec@gmail.com)
Date: Mon Oct 24 2005 - 19:32:03 EDT


hey

what about the "emb_limit" used with the "static" command?

http://www.cisco.com/en/US/products/sw/secursw/ps2120/products_command_reference_chapter09186a00801cd841.html#wp1026694
The embryonic connection limit lets you prevent a type of attack where
processes are started without being completed. When the embryonic
limit is surpassed, the TCP intercept feature intercepts TCP
synchronization (SYN) packets from clients to servers on a higher
security level.

cheers
Ivan

On 10/24/05, BSK <bishan4u@yahoo.co.uk> wrote:
> Hello Everyone,
>
> Just wanted some feedback from you people. I'm doing a
> Firewall Assessment for a CISCO PIX firewall. The
> firewall allows SYN, FIN, NULL and XMAS scans but
> blocks ACK scans (largely means its a stateful
> firewall).
>
> Now what do we do to block the scans that are allowed.
> I think it should be easy to block FIN, NULL and XMAS
> scans but how do we block or limit or workaround a SYN
> scan. 1 way that I think is probably blocking or
> limiting the packets from the source (using IDS/IPS)
>
> Looking ahead to some ideas, thoughts, hints.
>
> thns bshan
>
>
>
>
> ___________________________________________________________
> To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com
>
> ------------------------------------------------------------------------------
> Audit your website security with Acunetix Web Vulnerability Scanner:
>
> Hackers are concentrating their efforts on attacking applications on your
> website. Up to 75% of cyber attacks are launched on shopping carts, forms,
> login pages, dynamic content etc. Firewalls, SSL and locked-down servers are
> futile against web application hacking. Check your website for vulnerabilities
> to SQL injection, Cross site scripting and other web attacks before hackers do!
> Download Trial at:
>
> http://www.securityfocus.com/sponsor/pen-test_050831
> -------------------------------------------------------------------------------
>
>

------------------------------------------------------------------------------
Audit your website security with Acunetix Web Vulnerability Scanner:

Hackers are concentrating their efforts on attacking applications on your
website. Up to 75% of cyber attacks are launched on shopping carts, forms,
login pages, dynamic content etc. Firewalls, SSL and locked-down servers are
futile against web application hacking. Check your website for vulnerabilities
to SQL injection, Cross site scripting and other web attacks before hackers do!
Download Trial at:

http://www.securityfocus.com/sponsor/pen-test_050831
-------------------------------------------------------------------------------



This archive was generated by hypermail 2.1.7 : Sat Apr 12 2008 - 10:55:05 EDT