source: http://www.securityfocus.com/bid/18154/info

Geeklog is prone to multiple input-validation vulnerabilities. The issues include cross-site scripting and SQL-injection vulnerabilities. These issues are due to a failure in the application to properly sanitize user-supplied input. 

A successful exploit of these vulnerabilities could allow an attacker to compromise the application, access or modify data, steal cookie-based authentication credentials, or even exploit vulnerabilities in the underlying database implementation. Other attacks are also possible.

Geeklog version 1.4.0sr2 is vulnerable; other versions may also be affected.

http://www.example.com/geeklog/getimage.php?mode=show&image=./<IMG%20SRC=JaVaScRiPt:alert(document.cookie)>