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
Workload Security 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 Workload Security 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 Workload
Security to Automatically implement recommendations scan results.
Procedure
- Open the properties for the computer.
- Manually run an enhanced recommendation scan or a classic recommendation scan.
- Open the policy to which you want to assign the rules then complete the rule assignments.
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. Workload Security 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 Understanding the Generic SQL Injection Prevention rule.