Looking for mod_security rule against IIS WebDAV exploit.

Our servers are being hit with DoS via IIS WebDAV exploit. It runs up the CPU to about 40 until my hogkiller stops apache, etc.

This is the kind of stuff I see in the apache access_log:


"SEARCH /\x90\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\xc9\\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\" 414 271


SEARCH /\x90\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\x04H\

etc. etc. etc.

I am thinking there must be a mod_security ruleset I can apply against this?

 

Okay, I am reading that mod_security will not catch this early enough. So now I am thinking there must be a way to alter the BFD script so that the attacking IP is dropped into the firewall.

Thoughts/solutions anyone?

 

Okay, here apparently is at least one solution (using a redirect) from - http://aplawrence.com/Blog/B1234.html

Here's the part I just added to httpd.conf, then restarted apache and am hoping for the best:

# Send MS IIS Exploits to the company who makes them all possible!
<IfModule mod_rewrite.c>
RedirectMatch permanent (.*)cmd.exe(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)root.exe(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/_vti_bin\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/scripts\/\.\.(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/_mem_bin\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/msadc\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/MSADC\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/c\/winnt\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/d\/winnt\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/x90\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/xc9\/(.*)$ http://www.microsoft.com
RedirectMatch permanent (.*)\/x04H\/(.*)$ http://www.microsoft.com
</IfModule>

 

Just to follow up. This did not work. Any idea where I could insert the above redirects (other than in httpd.conf) to where they would work?