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Blocklisting files

The Blocklist feature allows you to effectively manage and control access to files and network connections identified as potential threats during incident investigations. By adding potentially harmful files to the blocklist, you ensure these files are prohibited from running on the network, mitigating the risk of damage or the spread of malicious software.

In the Blocklist page you can view and manage Blocklist rules. The activity records can be viewed in User activity log.

Note

The feature requires a Business Security Premium license, or any license that supports the EDR feature.

The Blocklist feature only works on Windows OSs.

In the data table, you can view the following details for each item:

  • Target company

  • Note

  • Created by

  • Date created

  • Rule type

  • Source type

  • Hash type

  • File name

  • File hash

  • Firewall rule name

  • Command line

  • Local IP/Mask

  • Remote IP/Mask

  • Local port/Port range

  • Remote port/Port range

  • Directly connected computers

  • Remote MAC

  • Protocol

  • Direction

  • IP version

Add rules to the Blocklist

Blocklist rules serve as guidelines or criteria for creating and managing a list of entities that are denied access for potential threats.

Adding hash values to the Blocklist

  1. Click the Add rule button at the top of the grid.

  2. From the dropdown select Application hash.

  3. Optionally you can type in a Note relevant to the Blocklist rule you are creating.

  4. Choose from MD5 or SHA256 and paste the value in the box below.

    Note

    Only executable files can be blocked by the Blocklist feature.

  5. Select the target companies for the Blocklist rule.

    Note

    The rule is added recursively for all valid companies that are using the EDR module.

    You can add up to 100.000 hash values to the Blocklist for your companies.

Blocklist_rules_add_hash_rule.png

Adding application path values to the Blocklist

Prerequisites

The Content Control module needs to be installed on the endpoint and Application blacklisting must be enabled in the policy of the endpoint for the Path based app blocklist to work on the endpoint.

  1. Click the Add rule button at the top of the grid.

  2. From the dropdown select Application path.

  3. Optionally you can type in a Note relevant to the Blocklist rule you are creating.

  4. Add the Application path in the specific field.

  5. Select the target companies for the Blocklist rule.

    Note

    The rule is added recursively for all valid companies.

    You can add up to 10.000 application path values to the Blocklist for your companies.

Blocklist_rules_add_app_path_rule.png

Adding connection rules to the Blocklist

Prerequisites

The Firewall module needs to be installed on the endpoint and enabled in the policy of the endpoint for the blocklist connection rules to work on a given endpoint.

  1. Click the Add rule button at the top of the grid.

    Note

    Blocklist rules will be executed before the policy rules. This means that any restrictions or allowances specified in the blocklist will take precedence over the general policy rules.

    The blocklist rules are unaffected by changes in the monitor process or adapter settings, and all rules will always be applicable to all adapters.

  2. From the dropdown select Connection.

  3. In the Add connection rule screen start filling in the required details:

    • Firewall rule name - Enter the name under which the rule will be listed in the rules table ( for example, the name of the application the rule applies to).

    • Note - Optionally you can type in a Note relevant to the Blocklist rule you are creating.

    • Application path - You can specify the path to the application executable file on the target companies.

      • Choose from the menu a predefined location and complete the path as needed.

        For example, for an application installed in the Program Files folder, select %ProgramFiles% and complete the path by adding a backslash (\) and the name of the application.

      • Enter the full path in the edit field.

        It is advisable to use system variables (where appropriate) to make sure the path is valid on all target computers.

    • Command line - If you want the rule to apply only when the specified application is opened with a specific command in the Windows command line interface, type the respective command in the edit field. Otherwise you can leave it blank.

    • Application MD5 - If you want the rule to check the application's file data integrity based on its MD5 hash code, enter it in the edit field. Otherwise, leave the field blank.

      Note

      Make sure that both the command line and the MD5 hash are correctly linked to the application's path. For the rule to function correctly, the application's file path must be accurately specified along with its MD5 hash and any related command line instructions.

  4. Select the Connection rule Settings you want to apply.

    • Local Address

      Can be set to IP or IP/Mask. Specify the local IP address, IP/Mask and port, the rule applies to.

      If you have more than one network adapter, you can clear the Any check box and type a specific IP address.

      Likewise, to filter connections on a specific port or port range, enter the desired port or port range in the corresponding field.

    • Remote Address

      Specify the remote IP address and port the rule applies to.

      To filter the traffic to and from a specific computer, clear the Any check box and type its IP address.

    • Apply rule only for directly connected computers

      You can filter access based on Mac address.

    • Protocol

      Select the IP protocol the rule applies to.

      • If you want the rule to apply to all protocols, select Any.

      • If you want the rule to apply to TCP, select TCP.

      • If you want the rule to apply to UDP, select UDP.

      • If you want the rule to apply to a specific protocol, select that protocol from the Other menu.

        Note

        IANA Assigned Internet Protocol Numbers are assigned by the Internet Assigned Numbers Authority (IANA).

        You can find the complete list of assigned IANA Assigned Internet Protocol Numbers at http://www.iana.org/assignments/protocol-numbers.

    • Direction

      Select the traffic direction the rule applies to.

      Direction

      Description

      Outbound

      The rule applies only for the outgoing traffic.

      Inbound

      The rule applies only for the incoming traffic.

      Both

      The rule applies in both directions.

    • IP version

      Select the IP version (IPv4, IPv6 or Any) the rule applies to.

  5. Select the target companies for the Blocklist rule.

    The rule is added recursively for all valid companies.

Note

You can add up to 1000 connection rules to each of your companies. If you encounter an issue when trying to add a large number of connection check the detailed list of the affected targets and companies provided in Control Center.

To resolve this, you can either select valid child companies as targets or return to the main grid and delete some of the old blocklists. Additionally, if you want to add some of the blocklists for child companies that were previously ignored, go back to the bottom target list, select only valid companies, and then try again.

Blocklist_rules_add_connection_rule.png

Import rules to Blocklists

Importing hash values to the Blocklist

  1. Click the Import CSV button.

  2. Browse for and select your CSV file.

  3. Click Save.

You may also import local CSV files from your device into the Blocklist page, but first you must make sure your CSV is valid.

To create a valid CSV file for import you must populate the first three columns with the following data:

  1. The first column of the CSV must contain the Hash type: either md5 or sha256.

  2. The second column must contain corresponding hexadecimal hash values.

  3. The third column may contain optional string information related to the Note column in the Blocklist page.

Note

Information corresponding to the other columns in the Blocklist page will be filled in automatically when importing the CSV file.

A note is considered valid if it has less than 256 characters.

Importing connection rules to the Blocklist

  1. Click Import at the upper side of the Rules table.

  2. In the new window, click Add and select the CSV file.

  3. Click Save. The table is populated with the valid rules.

The accepted CSV format will contain the following values:

Column number

Column value

Note

Accepted values

1

ruleName

Mandatory field

Note

The maximum allowed length is 256 characters.

Text

2

note

Optional field

Note

The maximum allowed length is 256 characters.

Text

3

path

Optional field

Note

The maximum allowed length is 260 characters.

Absolute paths, system variables and the system keyword.

4

commandLine

Optional field

5

applicationMD5

Optional field

Note

The maximum allowed length is 32 hexadecimal characters

MD5

6

protocol

Mandatory field

  • Any

  • TCP

  • UDP

  • Custom

7

customprotocol

Mandatory field

Note

This is required only if you previously chose custom for the protocol field.

The accepted values are the decimal values found here.

8

direction

Mandatory field

  • Both

  • Inbound

  • Outbound

9

ipVersion

Mandatory field

  • Any

  • IPv4

  • IPv6

10

localAddressAny

Mandatory field

Accepted values are Yes or No.

11

localAddressIpMask

Mandatory field

Note

This is a mandatory field only if you previously chose No for the localAddressAny field.

In this case you must enter any valid IP address or subnet.

Multiple entries can be added if separated by semicolon (;).

Valid IP addresses or subnets.

12

localAddressPortRange

Optional field

Note

Multiple entries can be added if separated by semicolon (;).

Any valid port number or port ranges are accepted (e.g.: 443-446).

13

remoteAddressAny

Mandatory field

Accepted values are Yes or No.

14

remoteAddressIpMask

Mandatory field

Note

This is a mandatory field only if you previously chose No for the remoteAddressAny field. In this case you must enter any valid IP address or subnet.

Valid IP addresses or subnets.

15

remoteAddressPortRange

Optional field

Note

Multiple entries can be added if separated by semicolon (;).

Any valid port number or port ranges (e.g.: 443-446) are supported.

16

directlyConnectedEnable

Mandatory field

Accepted values are Yes or No.

17

directlyConnectedRemoteMac

Optional field

You must add a value only if you previously chose Yes in the directlyConnectedEnable field.

Any valid MAC address is accepted, and up to 100 entries can be added if separated by semicolon (;).

Importing application path values to the Blocklist

  1. Click Import at the upper side of the Rules table.

  2. In the new window, click Add and select the CSV file.

  3. Click Save. The table is populated with the valid rules.

To create a valid CSV file for import you must follow these steps and populate the columns with the following data:

  1. The first column must contain valid application paths. A path is considered valid if it matches these criteria:

    • Contains less than 260 characters.

    • Contains the Windows absolute path.

    • Does not contain any wildcards

  2. The second column is optional and may contain the rule note.

    A note is considered valid if it has less than 256 characters.

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