Update ruleedit

This API supports Token-based authentication only.

Updates an existing detection rule.

You can use PUT or PATCH methods to update rules, where:

  • PUT replaces the original rule and deletes fields that are not specified.
  • PATCH updates the specified fields.

Request URLedit

PUT <kibana host>:<port>/api/detection_engine/rules

PATCH <kibana host>:<port>/api/detection_engine/rules

Request bodyedit

A JSON object with:

  • The id or rule_id field of the rule you want to update.
  • The fields you want to modify.

If you call PUT to update a rule, all unspecified fields are deleted. You cannot modify the id or rule_id values.

For PATCH calls any of the fields can be modified, whereas for PUT calls some fields are required.

Fields required for PUT callsedit

Name Type Description

description

String

The rule’s description.

name

String

The rule’s name.

risk_score

Integer

A numerical representation of the alert’s severity from 0 to 100, where:

  • 0 - 21 represents low severity
  • 22 - 47 represents medium severity
  • 48 - 73 represents high severity
  • 74 - 100 represents critical severity

severity

String

Severity level of alerts produced by the rule, which must be one of the following:

  • low: Alerts that are of interest but generally not considered to be security incidents
  • medium: Alerts that require investigation
  • high: Alerts that require immediate investigation
  • critical: Alerts that indicate it is highly likely a security incident has occurred

type

String

Data type on which the rule is based:

  • eql: EQL query (see Event Query Language).
  • query: query with or without additional filters.
  • saved_query: saved search, identified in the saved_id field.
  • machine_learning: rule based on a machine learning job’s anomaly scores.
  • threat_match: rule that matches event values with values in the specified Elasticsearch index.
  • threshold: rule based on the number of times a query matches the specified field.

Field required for query, threat-match and threshold rules PUT callsedit

Name Type Description

query

String

Query used by the rule to create alerts. For threat-match rules, only the query’s results are used to determine whether an alert is generated.

Field required for threshold rules PUT callsedit

Name Type Description

threshold

Object

Defines the field and threshold value for when alerts are generated, where:

  • cardinality (Array of length 1): The field on which the cardinality is applied.
  • cardinality.field (string, required): The field on which to calculate and compare the cardinality.
  • cardinality.value (integer, required): The threshold value from which an alert is generated based on unique number of values of cardinality.field.
  • field (string or string[], required): The field on which the threshold is applied. If you specify an empty array ([]), alerts are generated when the query returns at least the number of results specified in the value field.
  • value (integer, required): The threshold value from which an alert is generated.

Field required for saved-query rules PUT callsedit

Name Type Description

saved_id

String

Kibana saved search used by the rule to create alerts.

Field required for EQL rules PUT callsedit

Name Type Description

language

String

Must be eql.

Fields required for machine-learning rules PUT callsedit

Name Type Description

anomaly_threshold

Integer

Anomaly score threshold above which the rule creates an alert. Valid values are from 0 to 100.

machine_learning_job_id

String

Machine learning job ID the rule monitors for anomaly scores.

Fields required for threat-match rules PUT callsedit

Name Type Description

threat_index

String[]

Elasticsearch indices used to check which field values generate alerts.

threat_query

String

Query used to determine which fields in the Elasticsearch index are used for generating alerts.

threat_mapping

Object[]

Array of entries objects that define mappings between the source event fields and the values in the Elasticsearch threat index. Each entries object must contain these fields:

  • field: field from the event indices on which the rule runs
  • type: must be mapping
  • value: field from the Elasticsearch threat index

You can use Boolean and and or logic to define the conditions for when matching fields and values generate alerts. Sibling entries objects are evaluated using or logic, whereas multiple entries in a single entries object use and logic. See below for an example that uses both and and or logic.

Optional fields for all rule typesedit

Name Type Description

actions

actions[]

Array defining the automated actions (notifications) taken when alerts are generated.

author

String[]

The rule’s author.

building_block_type

String

Determines if the rule acts as a building block. By default, building-block alerts are not displayed in the UI. These rules are used as a foundation for other rules that do generate alerts. Its value must be default. For more information, refer to About building block rules.

enabled

Boolean

Determines whether the rule is enabled. Defaults to true.

false_positives

String[]

String array used to describe common reasons why the rule may issue false-positive alerts. Defaults to an empty array.

from

String

Time from which data is analyzed each time the rule executes, using a date math range. For example, now-4200s means the rule analyzes data from 70 minutes before its start time. Defaults to now-6m (analyzes data from 6 minutes before the start time).

interval

String

Frequency of rule execution, using a date math range. For example, "1h" means the rule runs every hour. Defaults to 5m (5 minutes).

license

String

The rule’s license.

max_signals

Integer

Maximum number of alerts the rule can create during a single execution. Defaults to 100.

meta

Object

Placeholder for metadata about the rule.

NOTE: This field is overwritten when you save changes to the rule’s settings.

note

String

Notes to help investigate alerts produced by the rule.

output_index

String

Index to which alerts created by the rule are saved. If unspecified alerts are saved to .siem-signals-<space_name> index, where <space_name> is the name of the Kibana space in which the rule exists.

references

String[]

Array containing notes about or references to relevant information about the rule. Defaults to an empty array.

tags

String[]

String array containing words and phrases to help categorize, filter, and search rules. Defaults to an empty array.

threat

threat[]

Object containing attack information about the type of threat the rule monitors, see ECS threat fields. Defaults to an empty array.

throttle

String

Determines how often actions are taken:

  • no_actions: Never
  • rule: Every time new alerts are detected
  • 1h: Every hour
  • 1d: Every day
  • 7d: Every week

Required when actions are used to send notifications.

version

Integer

The rule’s version number. If this is not provided, the rule’s version number is incremented by 1.

PATCH calls enabling and disabling the rule do not increment its version number.

Optional fields for query, threat-match and EQL rulesedit

Name Type Description

exceptions_list

Object[]

Array of exception containers, which define exceptions that prevent the rule from generating alerts even when its other criteria are met. The object has these fields:

  • id (string, required): ID of the exception container.
  • list_id (string, required): List ID of the exception container.
  • namespace_type (string required): Determines whether the exceptions are valid in only the rule’s Kibana space (single) or in all Kibana spaces (agnostic).
  • type (string, required): The exception type, which must be either a detection rule exception (detection) or an endpoint exception (endpoint).

Optional fields for threat-match rulesedit

Name Type Description

threat_filters

Object[]

Query and filter context array used to filter documents from the Elasticsearch index containing the threat values.

threat_indicator_path

String

Much like an ingest processor, users can use this field to define where their threat indicator can be found on their indicator documents. Defaults to threatintel.indicator.

Optional fields for query, threat-match and threshold rulesedit

Name Type Description

language

String

Determines the query language, which must be kuery or lucene. Defaults to kuery.

Optional fields for EQL, query and threshold rulesedit

Name Type Description

filters

Object[]

The query and filter context array used to define the conditions for when alerts are created from events. Defaults to an empty array.

index

String[]

Indices on which the rule functions. Defaults to the Security Solution indices defined on the Kibana Advanced Settings page (KibanaStack ManagementAdvanced SettingssecuritySolution:defaultIndex).

risk_score_mapping

Object[]

Overrides generated alerts' risk_score with a value from the source event:

  • field (string, required): Source event field used to override the default risk_score. This field must be an integer.
  • operator (string, required): Must be equals.
  • value(string, required): Must be an empty string ("").

rule_name_override

String

Sets which field in the source event is used to populate the alert’s signal.rule.name value (in the UI, this value is displayed on the Rules page in the Rule column). When unspecified, the rule’s name value is used. The source field must be a string data type.

severity_mapping

Object[]

Overrides generated alerts' severity with values from the source event:

  • field (string, required): Source event field used to override the default severity.
  • operator (string, required): Must be equals.
  • severity (string, required): Mapped severity value, must be low, medium, high, or critical.
  • value(string, required): Field value used to determine the severity.

timestamp_override

String

Sets the time field used to query indices. When unspecified, rules query the @timestamp field. The source field must be an Elasticsearch date data type.

Optional fields for EQL rulesedit

Name Type Description

event_category_field

String

Contains the event classification, such as process, file, or network. This field is typically mapped as a field type in the keyword family. Defaults to the event.category ECS field.

tiebreaker_field

String

Sets a secondary field for sorting events (in ascending, lexicographic order) if they have the same timestamp.

timestamp_field

String

Contains the event timestamp used for sorting a sequence of events. This is different from timestamp_override, which is used for querying events within a range. Defaults to the @timestamp ECS field.

actions schemaedit

These fields are required when calling PUT to modify the actions object:

Name Type Description

action_type_id

String

The action type used for sending notifications, can be:

  • .slack
  • .email
  • .pagerduty
  • .webhook

group

String

Optionally groups actions by use cases. Use default for alert notifications.

id

String

The connector ID.

params

Object

Object containing the allowed connector fields, which varies according to the connector type:

  • For Slack:

    • message (string, required): The notification message.
  • For email:

    • to, cc, bcc (string): Email addresses to which the notifications are sent. At least one field must have a value.
    • subject (string, optional): Email subject line.
    • message (string, required): Email body text.
  • For Webhook:

    • body (string, required): JSON payload.
  • For PagerDuty:

    • severity (string, required): Severity of on the alert notification, can be: Critical, Error, Warning or Info.
    • eventAction (string, required): Event action type, which can be trigger, resolve, or acknowledge.
    • dedupKey (string, optional): Groups alert notifications with the same PagerDuty alert.
    • timestamp (DateTime, optional): ISO-8601 format timestamp.
    • component (string, optional): Source machine component responsible for the event, for example security-solution.
    • group (string, optional): Enables logical grouping of service components.
    • source (string, optional): The affected system. Defaults to the Kibana saved object ID of the action.
    • summary (string, options): Summary of the event. Defaults to No summary provided. Maximum length is 1024 characters.
    • class (string, optional): Value indicating the class/type of the event.

threat schemaedit

These fields are required when calling PUT to modify the threat object:

Name Type Description

framework

String

Relevant attack framework.

tactic

Object

Object containing information on the attack type:

  • id - string, required
  • name - string, required
  • reference - string, required

technique

Object

Object containing information on the attack technique:

  • id - string, required
  • name - string, required
  • reference - string, required

Only threats described using the MITRE ATT&CKTM framework are displayed in the UI (ManageRulesRule name).

Example requestedit

Updates the threat object:

PATCH api/detection_engine/rules
{
  "rule_id": "process_started_by_ms_office_program_possible_payload",
  "threat": [
   {
      "framework": "MITRE ATT&CK",
      "tactic": {
         "id": "TA0001",
         "reference": "https://attack.mitre.org/tactics/TA0001",
         "name": "Initial Access"
      },
      "technique": [
         {
            "id": "T1193",
            "name": "Spearphishing Attachment",
            "reference": "https://attack.mitre.org/techniques/T1193"
         }
      ]
   }
  ]
}

Response codeedit

200
Indicates a successful call.

Response payloadedit

The rule’s updated JSON object, including the time the rule was updated and an incremented version number.

Example response:

{
  "created_at": "2020-01-05T09:56:11.805Z",
  "updated_at": "2020-01-05T09:59:59.129Z",
  "created_by": "elastic",
  "description": "Process started by MS Office program - possible payload",
  "enabled": false,
  "false_positives": [],
  "filters": [
    {
      "query": {
        "match": {
          "event.action": {
            "query": "Process Create (rule: ProcessCreate)",
            "type": "phrase"
          }
        }
      }
    }
  ],
  "from": "now-6m",
  "id": "4f228868-9928-47e4-9785-9a1a9b520c7f",
  "interval": "5m",
  "rule_id": "process_started_by_ms_office_program_possible_payload",
  "language": "kuery",
  "output_index": ".siem-signals-default",
  "max_signals": 100,
  "risk_score": 50,
  "name": "MS Office child process",
  "query": "process.parent.name:EXCEL.EXE or process.parent.name:MSPUB.EXE or process.parent.name:OUTLOOK.EXE or process.parent.name:POWERPNT.EXE or process.parent.name:VISIO.EXE or process.parent.name:WINWORD.EXE",
  "references": [],
  "severity": "low",
  "updated_by": "elastic",
  "tags": [
    "child process",
    "ms office"
  ],
  "related_integrations": [],       
  "required_fields": [],            
  "setup": "",                      
  "type": "query",
  "threat": [
    {
      "framework": "MITRE ATT&CK",
      "tactic": {
        "id": "TA0001",
        "reference": "https://attack.mitre.org/tactics/TA0001",
        "name": "Initial Access"
      },
      "technique": [
        {
          "id": "T1193",
          "name": "Spearphishing Attachment",
          "reference": "https://attack.mitre.org/techniques/T1193"
        }
      ]
    }
  ],
  "execution_summary": {                      
    "last_execution": {
      "date": "2022-03-23T16:06:12.787Z",
      "status": "partial failure",
      "status_order": 20,
      "message": "This rule attempted to query data from Elasticsearch indices listed in the \"Index pattern\" section of the rule definition, but no matching index was found.",
      "metrics": {
          "total_search_duration_ms": 135,
          "total_indexing_duration_ms": 15,
          "execution_gap_duration_s": 0,
      }
    }
  },
  "version": 2
}

[dev] This functionality is in development and may be changed or removed completely in a future release. These features are unsupported and not subject to the support SLA of official GA features. These fields are under development and their usage or schema may change: related_integrations, required_fields, setup, and execution_summary.