Enrichment rules

Name

Required setting.

Unique name of the resource. Must contain 1 to 128 Unicode characters.

Tenant

Required setting.

The name of the tenant that owns the resource.

Source kind

Required setting.

Drop-down list for selecting the type of incoming events. Depending on the selected type, you may see the following additional settings:

• constant

  This type of enrichment is used when a constant needs to be added to an event field. Settings of this type of enrichment:

  • In the Constant field, specify the value that should be added to the event field. The value may not be longer than 255 Unicode characters. If you leave this field blank, the existing event field value will be cleared.
  • In the Target field drop-down list, select the KUMA event field to which you want to write the data.

  If you are using the event enrichment functions for extended schema fields of "String", "Number", or "Float" type with a constant, the constant is added to the field.

  If you are using the event enrichment functions for extended schema fields of "Array of strings", "Array of numbers", or "Array of floats" type with a constant, the constant is added to the elements of the array.

   

• dictionary

  This type of enrichment is used if you need to add a value from the dictionary of the Dictionary type.

  When this type is selected in the Dictionary name drop-down list, you must select the dictionary that will provide the values. In the Key fields settings block, you must use the Add field button to select the event fields whose values will be used for dictionary entry selection.

  If you are using event enrichment with the "Dictionary" type selected as the "Source kind" setting, and an array field is specified in the "Key enrichment fields" setting, when an array is passed as the dictionary key, the array is serialized into a string in accordance with the rules of serializing a single value in the TSV format.

  Example: The "Key enrichment fields" setting uses the SA.StringArrayOne extended schema field. The SA.StringArrayOne extended schema field contains 3 elements: "a", "b" and "c". The following value is passed to the dictionary as the key: ['a','b','c'].

  If the "Key enrichment fields" setting uses an extended schema array field and a regular event schema field, the field values are separated by the "|" character when the dictionary is queried.

  Example: The "Key enrichment fields" setting uses two fields: the SA.StringArrayOne extended schema field and the Code field. The SA.StringArrayOne extended schema field contains 3 elements: "a", "b", and "c"; the Code string field contains the character sequence "myCode". The following value is passed to the dictionary as the key: ['a','b','c']|myCode.

   

• table

  This type of enrichment is used if you need to add a value from the dictionary of the Table type.

  When this enrichment type is selected in the Dictionary name drop-down list, select the dictionary for providing the values. In the Key fields group of settings, use the Add field button to select the event fields whose values are used for dictionary entry selection.

  In the Mapping table, configure the dictionary fields to provide data and the event fields to receive data:

  • In the Dictionary field column, select the dictionary field. The available fields depend on the selected dictionary resource.
  • In the KUMA field column, select the event field to which the value is written. For some of the selected fields (*custom* and *flex*), in the Label column, you can specify a name for the data written to them.

  New table rows can be added by using the Add new element button. Columns can be deleted using the button.

• event

  This type of enrichment is used when you need to write a value from another event field to the current event field. Settings of this type of enrichment:

  • In the Target field drop-down list, select the KUMA event field to which you want to write the data.
  • In the Source field drop-down list, select the event field whose value will be written to the target field.
  • In the Conversion settings block, you can create rules for modifying the original data before it is written to the KUMA event fields. The conversion type can be selected from the drop-down list. You can use the Add conversion and Delete buttons to add or delete a conversion, respectively. The order of conversions is important.

    Available conversions

    Conversions are changes that can be applied to a value before it gets written to the event field. The conversion type is selected from a drop-down list.

    Available conversions:

    • lower—is used to make all characters of the value lowercase
    • upper—is used to make all characters of the value uppercase
    • regexp – used to convert a value using the regular expression RE2. When this conversion type is selected, the field appears where regular expression should be added.
    • substring—is used to extract characters in the position range specified in the Start and End fields. These fields appear when this conversion type is selected.
    • replace—is used to replace specified character sequence with the other character sequence. When this type of conversion is selected, new fields appear:
      • Replace chars—in this field you can specify the character sequence that should be replaced.
      • With chars—in this field you can specify the characters sequence should be used instead of replaced characters.
    • trim—used to simultaneously remove the characters specified in the Chars field from the leading and end positions of the value. The field appears when this type of conversion is selected. For example, a trim conversion with the Micromon value applied to Microsoft-Windows-Sysmon results in soft-Windows-Sys.
    • append is used to add the characters specified in the Constant field to the end of the event field value. The field appears when this type of conversion is selected.
    • prepend—used to prepend the characters specified in the Constant field to the start of the event field value. The field appears when this type of conversion is selected.
    • replace with regexp—is used to replace RE2 regular expression results with the character sequence.
      • Expression—in this field you can specify the regular expression which results that should be replaced.
      • With chars—in this field you can specify the characters sequence should be used instead of replaced characters.
    • Converting encoded strings to text:
      • decodeHexString—used to convert a HEX string to text.
      • decodeBase64String—used to convert a Base64 string to text.
      • decodeBase64URLString—used to convert a Base64url string to text.

      When converting a corrupted string or if conversion error occur, corrupted data may be written to the event field.

      During event enrichment, if the length of the encoded string exceeds the size of the field of the normalized event, the string is truncated and is not decoded.

      If the length of the decoded string exceeds the size of the event field into which the decoded value is to be written, such a string is truncated to fit the size of the event field.

    Conversions when using the extended event schema

    Whether or not a conversion can be used depends on the type of extended event schema field being used:

    • For an additional field of the "String" type, all types of conversions are available.
    • For fields of the "Number" and "Float" types, the following types of conversions are available: regexp, substring, replace, trim, append, prepend, replaceWithRegexp, decodeHexString, decodeBase64String, decodeBase64URLString.
    • For fields of "Array of strings", "Array of numbers", and "Array of floats" types, the following types of conversions are available: append, prepend.

     

• template

  This type of enrichment is used when you need to write a value obtained by processing Go templates into the event field. Settings of this type of enrichment:

  • Put the Go template into the Template field.

    Event field names are passed in the {{.EventField}} format, where EventField is the name of the event field from which the value must be passed to the script.

    Example: Attack on {{.DestinationAddress}} from {{.SourceAddress}}.

  • In the Target field drop-down list, select the KUMA event field to which you want to write the data.

  To convert the data in an array field in a template into the TSV format, you must use the toString function.

  If you are using enrichment of events that have the "Template" type selected as the "Source kind" setting, in which the target field has the "String" type, and the source field is an extended event schema field containing an array of strings, you can use one of the following examples for the template.

  Example:

  {{.SA.StringArrayOne}}

  Example:

  {{- range $index, $element := . SA.StringArrayOne -}}

  {{- if $index}}, {{end}}"{{$element}}"{{- end -}}

   

• dns

  This type of enrichment is used to send requests to a private network DNS server to convert IP addresses into domain names or vice versa. IP addresses are converted to DNS names only for private addresses: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 100.64.0.0/10.

  Available settings:

  • URL—in this field, you can specify the URL of a DNS server to which you want to send requests. You can use the Add URL button to specify multiple URLs.
  • RPS—maximum number of requests sent to the server per second. The default value is 1,000.
  • Workers—maximum number of requests per one point in time. The default value is 1.
  • Max tasks—maximum number of simultaneously fulfilled requests. By default, this value is equal to the number of vCPUs of the KUMA Core server.
  • Cache TTL—the lifetime of the values stored in the cache. The default value is 60.
  • Cache disabled—you can use this drop-down list to enable or disable caching. Caching is enabled by default.
• cybertrace

  This type of enrichment is used to add information from CyberTrace data streams to event fields.

  Available settings:

  • URL (required)—in this field, you can specify the URL of a CyberTrace server to which you want to send requests.
  • Number of connections—maximum number of connections to the CyberTrace server that can be simultaneously established by KUMA. By default, this value is equal to the number of vCPUs of the KUMA Core server.
  • RPS—maximum number of requests sent to the server per second. The default value is 1,000.
  • Timeout—amount of time to wait for a response from the CyberTrace server, in seconds. The default value is 30.
  • Mapping (required)—this settings block contains the mapping table for mapping KUMA event fields to CyberTrace indicator types. The KUMA field column displays the names of KUMA event fields, and the CyberTrace indicator column displays the types of CyberTrace indicators.

    Available types of CyberTrace indicators:

    • ip
    • url
    • hash

    In the mapping table, you must provide at least one string. You can use the Add row button to add a string, and can use the button to remove a string.

• timezone

  This type of enrichment is used in collectors and correlators to assign a specific timezone to an event. Timezone information may be useful when searching for events that occurred at unusual times, such as nighttime.

  When this type of enrichment is selected, the required timezone must be selected from the Timezone drop-down list.

  Make sure that the required time zone is set on the server hosting the enrichment-utilizing service. For example, you can do this by using the timedatectl list-timezones command, which shows all time zones that are set on the server. For more details on setting time zones, please refer to your operating system documentation.

  When an event is enriched, the time offset of the selected timezone relative to Coordinated Universal Time (UTC) is written to the DeviceTimeZone event field in the +-hh:mm format. For example, if you select the Asia/Yekaterinburg timezone, the value +05:00 will be written to the DeviceTimeZone field. If the enriched event already has a value in the DeviceTimeZone field, it will be overwritten.

  By default, if the timezone is not specified in the event being processed and enrichment rules by timezone are not configured, the event is assigned the timezone of the server hosting the service (collector or correlator) that processes the event. If the server time is changed, the service must be restarted.

  Permissible time formats when enriching the DeviceTimeZone field

  When processing incoming raw events in the collector, the following time formats can be automatically converted to the +-hh:mm format:

  Time format in a processed event	Example
  +-hh:mm	-07:00
  +-hhmm	-0700
  +-hh	-07

  If the date format in the DeviceTimeZone field differs from the formats listed above, the collector server timezone is written to the field when an event is enriched with timezone information. You can create custom normalization rules for non-standard time formats.

• geographic data

  This type of enrichment is used to add IP address geographic data to event fields. Learn more about linking IP addresses to geographic data.

  When this type is selected, in the Mapping geographic data to event fields settings block, you must specify from which event field the IP address will be read, select the required attributes of geographic data, and define the event fields in which geographic data will be written:

  1. In the Event field with IP address drop-down list, select the event field from which the IP address is read. Geographic data uploaded to KUMA is matched against this IP address.

     You can use the Add event field with IP address button to specify multiple event fields with IP addresses that require geographic data enrichment. You can delete event fields added in this way by clicking the Delete event field with IP address button.

     When the SourceAddress, DestinationAddress, and DeviceAddress event fields are selected, the Apply default mapping button becomes available. You can use this button to add preconfigured mapping pairs of geographic data attributes and event fields.

  2. For each event field you need to read the IP address from, select the type of geographic data and the event field to which the geographic data should be written.

     You can use the Add geodata attribute button to add field pairs for Geodata attribute – Event field to write to. You can also configure different types of geographic data for one IP address to be written to different event fields. To delete a field pair, click .

     • In the Geodata attribute field, select which geographic data corresponding to the read IP address should be written to the event. Available geographic data attributes: Country, Region, City, Longitude, Latitude.
     • In the Event field to write to, select the event field which the selected geographic data attribute must be written to.

     You can write identical geographic data attributes to different event fields. If you configure multiple geographic data attributes to be written to the same event field, the event will be enriched with the last mapping in the sequence.

   

   

Debug

You can use this toggle switch to enable the logging of service operations. Logging is disabled by default.

Description

Resource description: up to 4,000 Unicode characters.

Filter

Group of settings in which you can specify the conditions for identifying events that must be processed by this resource. You can select an existing filter from the drop-down list or create a new filter.

Creating a filter in resources

Enrichment rule name

Description

[OOTB] KATA alert

Used to enrich events received from KATA in the form of a hyperlink to an alert.

The hyperlink is put in the DeviceExternalId field.