Security recommendations

Revision as of 10:54, 16 February 2006 by Helen (talk | contribs) (formatting)

Jump to: navigation, search

All web application software is highly complex, and every application has security issues that are found from time to time, usually involving some conbination of input that the programmers did not anticipate. The Moodle project takes security seriously, and is continuously improving Moodle to close such holes as we find them.

Before all

  • In this article, you will find important security measures for your Moodle installation.
  • You should report security problems directly at http://security.moodle.org - because developers might overlook it elsewhere, and they must not be released to general public until they are solved (to prevent attacks).
  • You should not post actual exploits in the bugtracker or forums, for exactly the same reasons.

Simple security measures

  • The best security strategy is a good backup! But you don't have a good backup unless you are able to restore it. Test your restoration procedures!
  • Load only software or services you will use
  • Perform regular updates
  • Model your security after the layers of clothing you wear on a cold winter day

Basic recommendations

  • Update Moodle regularly on each release
Published security holes draw crackers attention after release. The older the version, the more vulnerabilities it is likely to contain.
  • Disable register globals
This will help prevent against possible XSS problems in third-party scripts.
  • Use strong passwords for admin and teachers
Choosing "difficult" passwords is a basic security practice to protect against "brute force" cracking of accounts.
  • Only give teacher accounts to trusted users. Avoid creating public sandboxes with free teacher accounts on production servers.
Teacher accounts have much freer permissions and it is easier to create situations where data can be abused or stolen.
  • Separate your systems as much as possible
Another basic security technique is to use different passwords on different systems, use different machines for different services and so on. This will prevent damage being widespread even if one account or one server is compromised.

Run regular updates

  • Use auto update systems
  • Windows Update
  • Linux: up2date, yum, apt-get
Consider automating updates with a script scheduled via cron
  • Mac OSX update system
  • Stay current with php, apache, and moodle

Use mailing lists to stay updated

Firewalls

  • Security experts recommend a dual firewall
Differing hardware/software combinations
  • Disabling unused services is often as effective as a firewall
Use netstat -a to review open network ports
  • Not a guarantee of protection
  • Allow ports
80, 443(ssl), and 9111 (for chat),
Remote admin: ssh 22, or rpd 3389

Be prepared for the worst

Moodle security alerts

  • Register your site with Moodle.org
Registered users receive email alerts

Miscellaneous considerations

These are all things you might consider that impact your overall security:

  • Turn off opentogoogle, esp for K12 sites
  • Use SSL, httpslogins=yes
  • Disable guest access
  • Place enrollment keys on all courses
  • Use good passwords
  • Use the secure forms setting
  • Set the mysql root user password
  • Turn off mysql network access

Most secure/paranoid file permissions

Assuming you are running this on a sealed server (i.e. no user logins allowed on the machine) and that root takes care of the modifications to both moodle code and moodle config (config.php), then this are the most tight permissions I can think of:

1. moodledata directory and all of its contents (and subdirs, includes sessions):

owner: apache user (apache, httpd, www-data, whatever)
group: apache group (apache, httpd, www-data, whatever)
perms: 700 on directories, 600 on files

2. moodle directory and all of its contents and subdirs (including config.php):

owner: root
group: root
perms: 755 on directories, 644 on files.

If you allow local logins, then 2. should be:

owner: root
group: apache group
perms: 750 on directories, 640 on files

Think of these permissions as the most paranoid ones. You can be secure enough with less tighter permissions, both in moodledata and moodle directories (and subdirectories).

See also