Rule: -- Sid: 1455 -- Summary: This event is generated when an attempt is made to access a web application that may lead to exploitation of the application. -- Impact: Potentially harmful execution of binaries through perl open() -- Detailed Information: An open source calendar perl script by Matt Kruse, Allows commands to be executed without input verification using the perl open() function. ie /cgi-bin/calendar.pl place the string "|ping 127.0.0.1|" in the configuration file field, this executes the command "ping 127.0.0.1" -- Affected Systems: Any web server running the application. -- Attack Scenarios: An unauthenticated user can execute arbitrary programs on the server by accessing calendar.pl and inputting commands such as "|mail /etc/passwd|" into the configuration file field. -- Ease of Attack: Simple. No exploit software required. -- False Positives: If your webserver has pages by the name of calendar.pl this rule will fire often. Many sites now use calendar applications and this rule may generate a large number of false positives, it does not distinguish between perl cgi applications and php scripts. Consider tuning this rule for your site if it is generating a large number of false positives. If you use a calendar application, consider changing the name of the script to something other than "calendar.pl". -- False Negatives: None known. -- Corrective Action: Download a newer version of the cgi -- Contributors: Original Rule Writer Unknown Snort documentation contributed by Aaron Navratil (Initial Research) Snort documentation contributed by Josh Gray (Edits) Sourcefire Research Team Nigel Houghton <nigel.houghton@sourcefire.com> -- Additional References: CVE: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2000-0432 Bugtraq: http://online.securityfocus.com/bid/1215 --
