[Full-disclosure] Cisco Linksys WRT54G XSS Vulnerability

[Justin Klein Keane <justin@xxxxxxxxxxxx>]

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Description of Vulnerability:
- -----------------------------
Linksys WRT54G is a consumer wireless G broadband router and four port
switch (http://www.linksysbycisco.com/ANZ/en/support/WRT54G).  The
device provides an administration interface for configuration via a web
browser.  Unfortunately the interface does not sanitize keywords for
safe browsing leading to a stored/persistent cross site scripting (XSS)
vulnerability.

Systems affected:
- -----------------
Cisco Linksys Wireless G Boradband Router WRT54G with firmware version
4.21.1 was tested and found to be vulnerable.

Proof of Concept:
- -----------------
1.  Log into the WRT54G administration screen and navigate to /Filters.asp
2.  Enter "' onBlur='alert("xss")" for the "Website Blocking by Keyword"
value.
3.  Click the 'Save Settings' button at the bottom of the form, ignore
the error and click 'Continue'
4.  After the page refreshes click on the "Website Blocking by Keyword"
textfield then click outside to view the JavaScript alert

- -- 
Justin Klein Keane
http://www.MadIrish.net

The digital signature on this e-mail may be confirmed using the
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