Enable Intrusion Prevention and monitor network traffic for exploits using Detect
mode. When you are satisfied with how your Intrusion Prevention rules are assigned,
switch to Prevent mode.
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NoteThe configuration of your intrusion prevention system (IPS) affects system resources
like central processing unit (CPU) and random access memory (RAM). To optimize IPS
performance on the agent, see Performance tips for Intrusion Prevention.
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For an overview of Intrusion Prevention, see Block exploit attempts using Intrusion Prevention.
Enable Intrusion Prevention in Detect mode
Enable Intrusion Prevention and use Detect mode for monitoring. Configure Intrusion
Prevention using the appropriate policies to affect the targeted computers. You can
also configure individual computers.
For more fine-grained control when you assign Intrusion Prevention rules, you can
override the global behavior mode and configure specific rules to either prevent or
detect. See Override the behavior mode for a rule.
Procedure
- Go to .
- For Configuration, select one of the following:
-
On
-
Inherited (On) (See policies, inheritance, and overrides.)
-
- Select Detect for Intrusion Prevention Behavior.For information on enabling Intrusion Prevention for containers, see Apply your intrusion prevention settings.If the behavior settings are not available, Network Engine Mode may be set to Tap. (See Test Firewall rules before deploying them.)
- Click Save.
Enable Auto Apply core Endpoint & Workload rules
Server & Workload Protection assigns core Endpoint & Workload rules to this computer whenever Rule updates happen. However, any manually unassigned rules remain unassigned.
Trend Micro recommends that you enable this feature when you have the Endpoint license but disable this feature and use Recommendation scans with the Workload license.
Procedure
- Select Yes for Implement core Endpoint & Workload rules automatically.
- Click Save.
Test Intrusion Prevention
Verify that Intrusion Prevention is working properly before continuing with further
actions.
Procedure
- If you have an agent-based deployment, ensure you have a computer that has an agent running.
- Turn off Web Reputation to prevent it from interfering with Intrusion Prevention.
- In the Server & Workload Protection console, click Computers.
- Double-click the computer where you plan to test Intrusion Prevention.
- Click Web Reputation.
- Select Off
- Block bad traffic:
- Click Intrusion Prevention for the computer.
- On the General tab, select Prevent. If Prevent is unavailable, set Configuration to Inherited (On).
- Assign the European Institute for Computer Antivirus Research (EICAR) test policy:
- Click Intrusion Prevention for the computer.
- Click Assign/Unassign.
- Search for
1005924
. - Select 1005924 - Restrict Download of EICAR Test File Over HTTP.
- Click OK.
- Try to download the EICAR file. Intrusion Prevention should stop you from downloading
this file.
- On Windows, go to http://files.trendmicro.com/products/eicar-file/eicar.com.
- On Linux, enter this command:
curl -O http://files.trendmicro.com/products/eicar-file/eicar.com
- Review the Intrusion Prevention events for the computer:
- Select for the computer.
- Click Get Events to see events that have occurred since the last heartbeat.
- Look for an event with 1005924 - Restrict Download of EICAR Test File Over HTTP as the Reason. The presence of this event indicates that Intrusion Prevention is working.
- Revert your changes to return your system to its previous state:
- Turn on Web Reputation.
- Reset the Prevent or Detect option.
- Remove the EICAR policy from the computer.
Apply recommended rules
To maximize performance, only assign the Intrusion Prevention rules that your policies
and computers require. Use a recommendation scan to obtain a list of rules that are appropriate. Although recommendation scans are
performed for a specific computer, you can assign the recommendations to a policy that the computer uses. You can also configure Server & Workload Protection to Automatically implement recommendations scan results.
Procedure
- Open the properties for the computer.
- On the General tab under Recommendations, click Scan for Recommendations.
- Open the policy that you want to assign the rules to and complete the rule assignments (see Manually assign rules).
What to do next
After you apply Intrusion Prevention rules, monitor system performance and Intrusion
Prevention event logs. Monitor CPU, RAM, and network usage to verify that system performance
is still acceptable. If not, you can modify some settings and deployment aspects to
improve performance. (See Performance tips for Intrusion Prevention.)
Check Intrusion Prevention events
Monitor Intrusion Prevention events to ensure that rules are not matching legitimate
network
traffic. If a rule is causing false positives you
can unassign the rule. (See Assign and unassign rules.)
Procedure
- To see Intrusion Prevention events, click .
Enable fail open for packet or system failures
Intrusion Prevention includes a network engine that may block packets before Intrusion
Prevention rules can be applied. This could lead to performance issues. You can change
this behavior to allow packets when system or internal packet failures occur. For
details, see Enable fail open behavior.
Switch to Prevent mode
When you are satisfied that Intrusion Prevention is not finding false positives, configure
your policy to use Intrusion Prevention in Prevent mode to enforce rules and log related
events.
Procedure
- Go to .
- Select Prevent for Intrusion Prevention Behavior.
- Click Save.
HTTP Protocol Decoding rule
The HTTP Protocol Decoding rule is the most important rule in the Web Server Common
Application Type. This rule decodes the HTTP traffic before the other rules inspect
it. This rule also allows you to control various components of the decoding process.
This rule is required when you use any of the Web Application Common or Web Server
Common rules that require it. Server & Workload Protection automatically assigns this rule when it is required by other rules. Because each
web application is different, the policy that uses this rule should run in Detect mode for a period of time before switching to Prevent mode to determine if any configuration changes are required. Quite often, changes
are required to the list of illegal characters. Refer to the Knowledge Base for details on how to tune this rule.
Cross-site scripting and generic SQL injection rules
Two of the most common application-layer attacks are SQL injection and cross-site
scripting (XSS). Cross-site scripting and SQL injection rules intercept the majority
of attacks by default, but you may need to adjust the drop score for specific resources
if they cause false positives.
Both rules are smart filters that need custom configuration for web servers. If you
have output from a Web Application Vulnerability Scanner, you should leverage that
information when applying protection. For example, if the user name field on the login.asp
page is vulnerable to SQL injection, ensure that the SQL injection rule is configured
to monitor that parameter with a low threshold to drop on.
For more information, see https://success.trendmicro.com/en-us/solution/ka-0003649