Input validation vulnerability in WP-Cirrus 0.6.11

The WP-Cirrus plugin for WordPress is vulnerable to a security issue which could allow an attacker to access and modify parts of a website. The vulnerability exists in versions up to and including 0.6.11 and is caused by a lack of security checks on data entered into the plugin’s admin settings. If an attacker with administrator access was able to inject malicious code into the website then this code would be executed whenever a user visits a page containing the code. This vulnerability only affects multi-site installations or installations where a specific security setting has been disabled.