~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Software: FREESCO public http server - Running thttpd/2.05 09nov99 Vendor: http://www.freesco.org Versions: 2.05 Platforms: Unix Bug: Cross Site Scripting Vulnerabillity Risk: Low Exploitation: Remote with browser Date: 22 Jan 2004 Author: Rafel Ivgi, The-Insider e-mail: the_insider@mail.com web: http://theinsider.deep-ice.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1) Introduction 2) Bug 3) The Code ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ =============== 1) Introduction =============== thttpd is a free "Open Source" webserver that comes by default with unix systems such as FREEBSD and Linux. freesco edited thttpd and published their own version. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ====== 2) Bug ====== The Vulnerabillity is Cross Site Scripting. If an attacker will request the following url from the server http:///cgi/example?test= The vulnerabillity exists in the servers default cgi example. XSS appears and the server allows an attacker to inject & execute scripts. In the words of securityfocus.com : ~~~~~~~~~~~~~~~~~~~~~~~~~~ If all of these circumstances are met, an attacker may be able to exploit this issue via a malicious link containing arbitrary HTML and script code as part of the hostname. When the malicious link is clicked by an unsuspecting user, the attacker-supplied HTML and script code will be executed by their web client. This will occur because the server will echo back the malicious hostname supplied in the client's request, without sufficiently escaping HTML and script code. Attacks of this nature may make it possible for attackers to manipulate web content or to steal cookie-based authentication credentials. It may be possible to take arbitrary actions as the victim user. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ =========== 3) The Code =========== http:///cgi/example?test= ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ --- Rafel Ivgi, The-Insider http://theinsider.deep-ice.com "Things that are unlikeable, are NOT impossible."