Cisco Cisco Email Security Appliance C650 Guía Del Usuario
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User Guide for AsyncOS 9.7 for Cisco Email Security Appliances
Chapter 9 Using Message Filters to Enforce Email Policies
Attachment Scanning
The image analysis filter rule allows you to determine the actions to take based on the following verdicts:
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Clean: The image is free of inappropriate content. The image analysis verdict is computed on the
message as a whole, so a message without any images will receive a "clean" verdict if scanned.
message as a whole, so a message without any images will receive a "clean" verdict if scanned.
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Suspect: The image may contain inappropriate content.
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Inappropriate: The image contains inappropriate content.
These verdicts represent a numeric value assigned by the image analyzer algorithm to determine
probability of inappropriate content.
probability of inappropriate content.
The following values are recommended:
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Clean: 0 to 49
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Suspect: 50 to 74
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Inappropriate: 75 to 100
You can fine-tune image scanning by configuring the sensitivity setting, which helps reduce the number
of false positives. For example, if you find that you are getting false positives, you can decrease the
sensitivity setting. Or, conversely, if you find that the image scanning is missing inappropriate content,
you may want to set the sensitivity higher. The sensitivity setting is a value between 0 (no sensitivity)
and 100 (highly sensitive). The default sensitivity setting of 65 is recommended.
of false positives. For example, if you find that you are getting false positives, you can decrease the
sensitivity setting. Or, conversely, if you find that the image scanning is missing inappropriate content,
you may want to set the sensitivity higher. The sensitivity setting is a value between 0 (no sensitivity)
and 100 (highly sensitive). The default sensitivity setting of 65 is recommended.
Related Topics
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Tuning Image Analysis Settings
Procedure
Step 1
Go to Security Services > IronPort Image Analysis.
Step 2
Click Edit Settings.
Step 3
Configure the settings for image analysis sensitivity. The default sensitivity setting of 65 is
recommended.
recommended.
Step 4
Configure the settings for Clean, Suspect, and Inappropriate verdicts.
When you configure the value ranges, ensure that you do not overlap values and that you use whole
integers.
integers.
Step 5
Optionally, configure AsyncOS to bypass scanning images that do not meet a minimum size requirement
(recommended). By default, this setting is configured for 100 pixels. Scanning images that are smaller
than 100 pixels can sometimes result in false positives.
(recommended). By default, this setting is configured for 100 pixels. Scanning images that are smaller
than 100 pixels can sometimes result in false positives.
You can also enable image analysis settings from the CLI using the
imageanalysisconfig
command:
Related Topics
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