Rafel Ivgi has discovered multiple vulnerabilities in Invision Power Board, allowing malicious people to conduct cross-site scripting attacks.

The vulnerabilities are caused due to missing validation of input passed to the "c", "showtopic", "f", "showuser", and "username" parameters. These can be exploited to execute arbitrary HTML and script code in a user's current browser session in context of a vulnerable site.

Examples:
http://[host]/?c='><script>alert(document.domain)</script>
http://[host]/?showtopic='><script>alert(document.domain)</script>
http://[host]/?act=SR&f='><script>alert(document.cookie)</script>
http://[host]/?showuser='><script>alert(document.cookie)</script>
http://[host]/index.php?act=Reg&CODE=2&coppa_user=0&UserName='><script>alert(document.cookie)</script>

Successful exploitation may result in exposure of various information (eg. cookie-based authentication information) associated with the site running Invision Power Board or inclusion of malicious content, which the user thinks is part of the real website.

The vulnerabilities have been reported in versions 1.3 and 1.3.1 Final. Other versions may also be affected.

Solution
Edit the source code to ensure that user input is properly sanitised.
Further details available to Secunia VIM customers

Provided and/or discovered by
Rafel Ivgi

Changelog
Further details available to Secunia VIM customers

Deep Links
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