GEN:SID 1:1998
Message WEB-PHP calendar.php access
Summary This event is generated when an attempt is made to exploit a known
vulnerability in a PHP web application running on a server.
Impact Information gathering and system integrity compromise. Possible unauthorized
administrative access to the server or application. Possible execution
of arbitrary code of the attackers choosing in some cases.
Detailed Information This event is generated when an attempt is made to access the file
calendar.php. Multiple applications are vulnerable to SQL injection
techniques that may lead to the execution of SQL code of the attackers
choosing.
Affected Systems All systems running PHP calendar applications
    VBulletin
    Invision Power Board
Attack Scenarios An attacker can manipulate user supplied variables to include SQL code
of their choosing in the request to a vulnerable application.
Ease of Attack Simple. Exploits exist.
Corrective Action Ensure the system is using an up to date version of the software and has
had all vendor supplied patches applied.
Additional References  
Rule References bugtraq: 5820
bugtraq: 9353
nessus: 11179