Re: Question about HTTP DDOS attacks.

From: Kyle R. Hofmann (krhat_private)
Date: Mon Mar 18 2002 - 10:26:35 PST

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    On Mon, 18 Mar 2002 07:42:47 +0100, Hugo van der Kooij wrote:
    > On Fri, 15 Mar 2002 eaxat_private wrote:
    > 
    > > For the last couple days, one of our client's virtual-hosts on one of our webservers has been DDOSed with
    > > tons of HTTP requests composed of:
    > > 
    > > GET / HTTP/1.1
    > > Host: example.com
    > 
    > These are in fact valid request if I setup a link like: <a 
    > href="http://example.com/"> or even <a href="http://example.com">
    
    They're not valid if he's not example.com.  See RFC 2606:
    
    "3. Reserved Example Second Level Domain Names
    
       The Internet Assigned Numbers Authority (IANA) also currently has the
       following second level domain names reserved which can be used as
       examples.
    
    	example.com
    	example.net
    	example.org"
    
    $ dig example.com
    
    ; <<>> DiG 2.2 <<>> example.com 
    ;; res options: init recurs defnam dnsrch
    ;; got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 38839
    ;; flags: qr rd ra; Ques: 1, Ans: 1, Auth: 2, Addit: 0
    ;; QUESTIONS:
    ;;	example.com, type = A, class = IN
    
    ;; ANSWERS:
    example.com.	172800	A	192.0.34.72
    
    ;; AUTHORITY RECORDS:
    example.com.	21600	NS	a.iana-servers.net.
    example.com.	21600	NS	b.iana-servers.net.
    
    ;; Total query time: 400 msec
    ;; FROM: yvonne.lemniscate.net to SERVER: default -- 127.0.0.1
    ;; WHEN: Mon Mar 18 10:22:35 2002
    ;; MSG SIZE  sent: 29  rcvd: 93
    
    $ lynx -dump http://www.example.com/
    
       You have reached this web page by typing "example.com", "example.net",
       or "example.org" into your web browser.
       
       These domain names are reserved for use in documentation and are not
       available for registration.
    
    -- 
    Kyle R. Hofmann <krhat_private>
    
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