Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

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User Guide for AsyncOS 9.8 for Cisco Email Security Appliances
 
Chapter 13      Anti-Spam
  Defining Anti-Spam Policies
Configuration Examples: Actions for Positively Identified versus Suspected 
Spam 
The aggressive example tags only suspected spam messages, while dropping those messages that are 
positively identified. Administrators and end-users can check the subject line of incoming message for 
false positives, and an administrator can adjust, if necessary, the suspected spam threshold. 
In the conservative example, positively identified and suspected spam is delivered with an altered 
subject. Users can delete suspected and positively identified spam. This method is more conservative 
than the first.
For a further discussion of aggressive and conservative policies in mail policies, see 
 in the Mail Policies chapter. 
Unwanted Marketing Messages From Legitimate Sources
If you had configured Marketing Email Settings under anti-spam settings for a mail policy, after 
upgrading to AsyncOS 9.5 for Email, Marketing Email Settings under anti-spam settings will be moved 
under graymail settings of the same policy. See 
Using Custom Headers to Redirect URLs in Suspected Spam to the Cisco Web 
Security Proxy: Configuration Example 
You can rewrite URLs in suspected spam so that when a recipient clicks a link in the message, the request 
is routed through the Cisco Web Security proxy service, which evaluates the safety of the site at click 
time and blocks access to known malicious sites. 
Before You Begin 
Enable the URL Filtering feature and its prerequisites. See 
Procedure 
Step 1
Apply a custom header to suspected spam messages: 
a.
Select Mail Policies > Incoming Mail Policies
b.
Click the link in the Anti-Spam column for a policy such as the Default policy. 
c.
In the Suspected Spam Settings section, enable suspected spam scanning.
Spam
Sample Actions 
(Aggressive) 
Sample Actions
(Conservative)
Positively 
Identified
Drop
Deliver with “
[Positive Spam]
” added 
to the subject of messages, or 
Quarantine 
Suspected 
Deliver with “
[Suspected Spam]
” 
added to the subject of messages
Deliver with “
[Suspected Spam]
” added to 
the subject of messages