by Robert Chartier by Robert Chartier
Give this a shot, and see how easy it is to spoof the Referer during a Web Request:

0.	Start, Run, Telnet <enter>
1.	Terminal, Preferences...
2.	Make sure that "Local Echo" is checked
3.	Connect, Remote System...
4.	Host Name: www.learnasp.com
5.	Port: 80
6.	<connect>
7.
8.
9.
10.	Type in (exactly):
11.	GET /learn/test/servereach.asp HTTP/1.1<enter>
12.	Host: www.learnasp.com<enter>
13.	Referer: http://www.aspfree.com/devlinks<enter><enter>
14.
15.

If you type it in correctly, you should see the response from the server in the form of HTML. You should notice right away that it reports the HTTP_REFERER:http://www.aspfree.com/devlinks. Now try the exact same thing, but change te Referer to anything you wish. Notice the ouput of the page also changes to reflect this new referer.



Bottom line, never trust the Referer server variable.






References:

Copy Source:

Start, Run, Telnet <enter>Terminal, Preferences...Make sure that "Local Echo" is checked Connect, Remote System...Host Name: www.learnasp.comPort: 80<connect>Type in (exactly):GET /learn/test/servereach.asp HTTP/1.1<enter>Host: www.learnasp.com<enter>Referer: http://www.aspfree.com/devlinks<enter><enter>

DISCLAIMER: The content provided in this article is not warranted or guaranteed by Developer Shed, Inc. The content provided is intended for entertainment and/or educational purposes in order to introduce to the reader key ideas, concepts, and/or product reviews. As such it is incumbent upon the reader to employ real-world tactics for security and implementation of best practices. We are not liable for any negative consequences that may result from implementing any information covered in our articles or tutorials. If this is a hardware review, it is not recommended to open and/or modify your hardware.

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