IPCop Cross Site Scripting Vulnerability in "proxylog.dat" http://www.kurczaba.com/html/security/0411291.htm ---------------------------------------------------------- Overview: "IPCop implements existing technology, secure programming practices and outstanding new concepts to make it ‘the’ Linux Distribution for protecting single home computers, to large corporate networks from intrusions and attacks." -http://www.ipcop.org Vendor: IPCop (http://www.ipcop.org) Affected Systems/Configuration: 1.4.1, possibly older versions Vulnerability/Exploit: A Cross Site Scripting vulnerability has been found in the IPCop web interface. The "proxylog.dat" page allows the IPCop administrators to review browsed websites that have been processed through Squid. By creating a specially crafted HTTP request, it is possible to inject script code into the "proxylog.dat" page. The variables "$url" and "$part" are not sanitized before being sent to the user. When the administrators view the page, the script code will be executed. Proof of Concept: The following HTTP request example will cause script injection into the proxy log: -----START PoC----- GET / HTTP/1.1 Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */* Accept-Language: en-us Accept-Encoding: gzip, deflate User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1) Host: example.com Connection: Close -----END PoC------- Workaround: 1) Open /home/httpd/cgi-bin/logs.cgi/proxylog.dat 2) Locate the following text: unless (length($part) < 60) { $part = "${part}..."; } 3) Insert the following five lines below: #Filter out < and > $url =~s//>/g; $part =~s/>/>/g; Date Discovered: November 29, 2004 Severity: Low Credit: Paul Kurczaba Kurczaba Associates