Security Incidents mailing list archives
RE: Tracking down the still infected hosts
From: "Fulton L. Preston Jr." <fulton () prestons org>
Date: Mon, 24 Sep 2001 22:00:53 -0400
I implemented the methods below on my IIS and Apache servers and it knocked all the local Nimda traffic dead in minutes. Nimda traffic from neighboring ISPs was way down within an hour. Since I am on a cable modem I can't control the rest of the network around me but this sure did shut them noisy infected boxes up in a hurry :) The only ones still hitting me (though very slowly now) are workstations that don't have IIS running but are still infected via other means. The boxes that are running IIS even stop responding to pings after awhile so I assume they die after awhile. It's stuff like this that makes the SecurityFocus mailing lists so darn useful! -----Original Message----- From: Mike Lewinski [mailto:mike () rockynet com] Sent: Monday, September 24, 2001 12:29 To: incidents () securityfocus com Subject: Re: Tracking down the still infected hosts
Anyone else doing anything to help this?
I don't think that this has been posted here yet.... The following appears to cripple infected hosts and limits the damage they can cause. Others who have used this report that persistent infected hosts disappear from their logs shortly after applying this configuration change to their own servers, and that browsing an infected server after applying this results in "HTTP 403.9 - Access Forbidden: Too many users are connected" For Apache: RedirectMatch (.*)\cmd.exe$ http://127.0.0.1 For IIS: ----- Original Message ----- From: "Ron Hornbaker" <ron () hksi net> To: <imail () hksi net> Sent: Friday, September 21, 2001 1:11 PM Subject: RE: [imail] IIS Judo against Nimda's DoS attacks (was Fwd: [isp-linux] Buaaa Haaa Ha Haaaaaaaaa...)
Great tip, Len. Here's the IIS version... just create a file in your
web
root called something like "Custom404.asp", with this content
(customize
the friendly part as much as you wish):
<% 'Custom404.asp page to thwart Nimda DoS attacks on IIS 'by Humankind Systems, Inc. http://hksi.net/ 'No support or guarantees of any kind are granted with this 'code. Use at your own risk. Distribute freely. 'Get the entire URL requested myRequest=Request.ServerVariables("QUERY_STRING") 'A list of filenames Nimda looks for myBadList="cmd.exe,root.exe,admin.dll,default.ida" 'Detect a GET request from the Nimda virus and take appropriate action arrBadString=Split(myBadList,",") for i=0 to UBound(arrBadString) if inStr(myRequest,arrBadString(i))>0 then 'turn offending server back on itself Response.redirect "http://127.0.0.1" end if next %> <html> <head> <title>Page Not Found</title> </head> <body> Sorry, but that page was not found on our server. <p> Here is a link back to our <a href="/">Home Page</a>. </body> </html> ------------------------------------------------------------------------ ---- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com ---------------------------------------------------------------------------- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com
Current thread:
- Tracking down the still infected hosts Darren Windham (Sep 24)
- Re: Tracking down the still infected hosts Mike Lewinski (Sep 24)
- <Possible follow-ups>
- RE: Tracking down the still infected hosts Martinez, Simon (Sep 24)
- RE: Tracking down the still infected hosts Fulton L. Preston Jr. (Sep 24)
- RE: Tracking down the still infected hosts Ryan McDonnell (Sep 25)
- Re: Tracking down the still infected hosts Kyle R. Hofmann (Sep 25)
- Re: Tracking down the still infected hosts Tina Bird (Sep 25)
- Re: Tracking down the still infected hosts Skip Carter (Sep 25)
- Re: Tracking down the still infected hosts Kyle R. Hofmann (Sep 25)
- Re: Tracking down the still infected hosts Dale Lancaster (Sep 25)
- Re: Tracking down the still infected hosts Duncan Hill (Sep 25)
- Re: Tracking down the still infected hosts Josh Burroughs (Sep 25)
- Message not available
- Re: Tracking down the still infected hosts Nicole Haywood (Sep 25)
- Re: Tracking down the still infected hosts Ryan Russell (Sep 25)