Linksys WRT54G XSS Vulnerability
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.
Cisco Linksys Wireless G Boradband Router WRT54G with firmware version 4.21.1 was tested and found to be vulnerable.
Proof of Concept:
- Log into the WRT54G administration screen and navigate to /Filters.asp
- Enter "' onBlur='alert("xss")" for the "Website Blocking by Keyword" value.
- Click the 'Save Settings' button at the bottom of the form, ignore the error and click 'Continue'