source: http://www.securityfocus.com/bid/24934/info

Insanely Simple Blog is prone to multiple input-validation vulnerabilities, including cross-site scripting, HTML-injection, and SQL-injection issues, because the application fails to properly sanitize user-supplied input.

Exploiting these issues could allow an attacker to steal cookie-based authentication credentials, execute arbitrary script code in the context of the webserver process, steal cookie-based authentication credentials, compromise the application, obtain sensitive information, access or modify data, or exploit latent vulnerabilities in the underlying database.

Insanely Simple Blog 0.5 and prior versions are vulnerable. 

http://www.example.com/index.php?current_subsection=2 or 1=1/*
http://www.example.net/index.php?current_subsection=2%20union%20all%20select blah from content/*