Installation security hints/nl

Algemeen

LimeSurvey relies on its own security, which is activated by default. The authors of this software take no responsibility and makes no claims regarding the appropriateness or security level of this software. However, we take security issues very seriously and react quickly. Therefore, if you know of any security problems within LimeSurvey, please let us know either by sending us an email to info@limesurvey.org or by opening a bug report in our bug tracker (please mark it as private).

Linux bestandsrechten

If you are using a Linux server, setting file permissions accordingly is required to secure your LimeSurey installation.

Linux/*nix bestandsrechten

Een Linux/*nix systeem is multiuser. Dat betekent dat er behalve jouw account mogelijk ook andere "gebruikers" actief zijn op het systeem. Deze "gebruikers" moeten de juiste rechten hebben.

Hint: setting file permissions is especially important in order to secure configuration files holding critical data such as passwords.

Het 'root'-account geeft altijd toegang tot alle bestanden (ongeacht de toegekende rechten), omdat het de super-admin is,

The web server (which runs LimeSurvey) is also running under a given identity (user). On Linux, this is usually the 'www', 'www-data' (on Debian/Ubuntu), 'apache' or 'nobody' user. However, some hosting companies use systems (such as suexec) that make it possible to run LimeSurvey scripts with your personal user. Of course, the web server user must have the right to read LimeSurvey files. However, only a small subset of LimeSurvey sub-directories must be writable by the web server user.

Hint: it is very valuable to revoke write permission for the web server user to these LimeSurvey sub-directories that do not require it. Indeed, even if a LimeSurvey vulnerability might be discovered, the main files will still be protected from an illicit modification thanks to the file system permissions.

Instellen van bestandsrechten op een Linuxsysteem in eigen beheer

If you're managing your web server and operating system configuration (you are the owner of the physical server or are renting a virtual server on which you have root access), you may consider the following recommendations from below.

You can first set the owner and group of your LimeSurvey files so that it will ease the file permissions setup. A possible strategy is to set the owner of the LimeSurvey files to your personal username, and the group of the LimeSurvey files to the web server group. Usually, this web server group only contains the web server account (and possibly another webmaster account). For instance, if your username is 'myaccount' and the webserver user is 'apache' in the 'apache' group, then, from a shell access, you can use the following command: $ chown -R myaccount:apache limesurvey/. Subsequently, set the file and sub-directories permissions.

For the script to work properly, the write access to some directories is needed:

• The /limesurvey/application/config directory requires Read & Write for saving the application configuration settings
• The /limesurvey/tmp directory and its sub-directories are used for imports/uploads and should be set to Read & Write for your web server
• The upload/directory and all its sub-directories must also have set Read & Write permissions in order to enable pictures and media files upload
• All other directories and files can be set to Read Only

Hint: supposing you've followed the recommendations above on owner/group, these settings can be applied by the following commands:

$ chmod -R o-r-w-x limesurvey/

$ chmod -R -w limesurvey/

$ chmod -R 770 limesurvey/application/config

$ chmod -R 770 limesurvey/tmp

$ chmod -R 770 limesurvey/upload

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Instellen van bestandsrechten op een beheerde webserver

Het is lastig om een standaardprocedure te geven voor een webapplicatie op een host, de inrichting kan veel verschillen.

In the managed server case, the server needs write access to some directories in order for the script to work properly:

• The /limesurvey/tmp directory is used for imports/uploads and should be set to Read & Write for your web server
• The upload/directory and all its sub-directories must also have Read & Write for your web server in order to enable pictures and media files upload
• The other directories and files should be set to Read Only

Hint:

• Depending on your web server configuration, you will have to chmod the rights on the writable folders to 755 or 777 to make it writable for the web server. Try 755 first, if it does not work, 'upgrade' to 777
• You can also try to remove other users' read access to config.php by setting this file's permissions to 750 - if it does not work, 'upgrade' to 755

Windows bestandsrechten

Als je een server op basis van Windows gebruikt, verzeker je er dan van dat alleen de eigenaar van het webserver-proces bestanden in de admin-directory kan schrijven. Op alle andere bestanden volstaan de lees- en uitvoerrechten.

Andere beveiligingszaken

The following are recommendations only. LimeSurvey in general is very safe without these additional measures. If you however collect extremely sensitive data, a little additional security can help:

SSL gebruik

Voor het gebruik van gevoelige gegevens bevelen we het gebruik van SSL aan. U kunt SSL meestal inschakelen door uw webserver goed in te stellen en een SSQL certificaat te gebruiken. Indien uw SSL heeft ingeschakeld dient u het gebruik van SSL af dwingen in de algemene instellingen van LimeSurvey. U kunt dan ook instellen dat alleen 'secure' cookies gebruikt worden, dit gaat met de respective option in config.php.

Toegang tot het bestand config.php

  U moet het bestand application/config/config.php pas na de eerste werkende installatie aanpassen.

De /application/config/config.php bevat een naam en wachtwoord voor de database server. Dit kan een beveiligingsprobleem zijn, zeker als je een login gebruikt die (te)veel in de database "mag". Mocht deze dus op straat komen te liggen, dan ben je heel misschien meer data kwijt dan alleen de enquêtes. Daarom kun je beter een specifiek account gebruiken dat alleen op de LimeSurvey database rechten heeft.

Another way to secure this information can be to put the information from the /application/config/config.php file in a non-web directory, i.e. for Apache users this is the directory above the htdocs (also known as public_html or www) folder. Basically, you will use config.php, but have one line in it - a line that includes the file with ACTUAL configuration information (ex: <?php return include("/home/hostfolder/safedata/configreal.php"); ?>). Remove all actual configuration information from /application/config/config.php and paste it into the other file (configreal.php) that is mentioned in the /application/config/config.php file. This other file should be located in a non-web directory. Then, /application/config/config.php will not contain database passwords etc. - just the name of the file that DOES contain the database info.

This avoids having to change all the other files that include /application/config/config.php, since config.php 're-directs them' towards the configuration file that is located in a non-web directory which includes all the real configuration information. However, you will need to edit configreal.php and change the follow parameters to use absolute directory paths to work properly:

'basePath' => dirname(dirname('''FILE''')),
'runtimePath' => dirname(dirname(dirname('''FILE'''))).DIRECTORY_SEPARATOR.'tmp'.DIRECTORY_SEPARATOR.'runtime',
[...]

'urlManager' => array(
   [...]
   'rules' => require('routes.php'),
   [...]
);

Voorbeeld:

'basePath' => '/var/www/htdocs/limesurvey',
'runtimePath' => '/var/www/htdocs/limesurvey/tmp/runtime',
[...]

'urlManager' => array(
   [...]
   'rules' => require('/var/www/htdocs/limesurvey/config/routes.php'),
   [...]
);

Also, don't use "admin" as the default user. Go to your MySQL database (or the one in which you installed LimeSurvey) and change default user name "admin" to whatever you prefer (e.g. "admin_xyz"). It will now be much harder to guess the administrator's new user name. Remember, this is one of the two variables intruders can use to gain access. The admin password is the other variable. So choose both of them with extreme caution.