Date: Sun, 16 May 0100 06:37:16 +0000 From: suid@SUID.KG Subject: Vuln in calender.pl (Matt Kruse calender script) To: BUGTRAQ@SECURITYFOCUS.COM Evening, I wouldnt normally post a small thing like this to bugtraq but i checked out cgi-resources.com and it seems to be damn popular so someone here may care. Oh yeah I notified Matt (the vendor) and he figured it wasnt really an issue. Oh well. Visit www.suid.kg/advisories/ for more crap like this. firstname.lastname@example.org --cut-- email@example.com - Matt Kruse Calendar Script Vulnerability Software: Matt Kruse Calendar Script URL: http://www.mattkruse.com/scripts/calendar/ Version: Version 2.2 and below? Platforms: UNIX / Windows NT Type: Input Validation Failure Lame Factor: Damn High Summary: Remote users can execute arbitrary commands on the web server with the priviledge level of the httpd process. Vulnerability: Both the calender.pl and the calendar_admin.pl scripts fail to perform proper input validation. The calender_admin.pl script for example prompts the user for a configuration file to modify. Then in an attempt to authenticate the user to verify they have access to modify the specified configuration file, it passes the user input straight to perl open(). *yoink*(tm) Exploit: calender_admin.pl - easiest Assuming http://www.ownable.domain/ has calender.pl at: http://www.ownable.domain/cgi-bin/calender.pl The admin script by default is at: http://www.ownable.domain/cgi-bin/calender_admin.pl Going to that URL will result in a username/password/configuration file input fields. Ignoring username and password, enter: |<command here>| (With the pipes) in the configuration file field. e.g. |ping 127.0.0.1| Note: I notice that calender.pl does not sanitise input either and is vulnerable to an open attack but am not interested enough to write about it. Blah. Greets: duke - WHAT THE HELL!?>! horizons yowie !