Руководство Пользователя для Cisco Cisco Email Security Appliance C170

This section contains some real world examples of filters with a brief discussion of each.

This filter bounces messages with addresses using 

%

, extra 

@

, and 

!

 characters in email addresses:

user%otherdomain@validdomain

user@otherdomain@validdomain:

domain!user@validdomain

Cisco IronPort appliances are not susceptible to these third party relay hacks that are often used to 
exploit traditional Sendmail/Qmail systems. As many of these symbols (for example 

%

) can be part of a 

perfectly legal email address, Cisco IronPort appliances will accept these as valid addresses, verify them 
against the configured recipient lists, and pass them on to the next internal server. Cisco IronPort 
appliances do not relay these messages to the world.

These filters are put in place to protect users who may have open-source MTAs that are misconfigured 
to allow relay of these types of messages.

You can also configure a listener to handle these types of addresses. See 

 for more information.

This filter sends notification based on whether the subject contains specific words:

sourceRouted: 

if (rcpt-to == "(%|@|!)(.*)@") {

  bounce();

}

search_for_sensitive_content:

if (Subject == "(?i)plaintiff|lawsuit|judge" ) {

    notify ("admin@company.com");

}