Detection rules › YARA-L

OneLogin Multiple Users Login Failures From The Same IP

Severity
medium
Type
Alert
Time window
1h
Match by
ip
Author
Google Cloud Security
Source
github.com/chronicle/detection-rules

Detects multiple users login failures from a single IP.

MITRE ATT&CK coverage

TacticTechniques
Initial AccessT1078.004 Valid Accounts: Cloud Accounts

Rule body yaral

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 * Copyright 2024 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

rule onelogin_multiple_users_login_failures_from_the_same_ip {

  meta:
    author = "Google Cloud Security"
    description = "Detects multiple users login failures from a single IP."
    rule_id = "mr_8e302561-6fc5-430d-ae0c-bd285a0aec21"
    rule_name = "OneLogin Multiple Users Login Failures From The Same IP"
    mitre_attack_tactic = "Initial Access"
    mitre_attack_technique = "Valid Accounts: Cloud Accounts"
    mitre_attack_url = "https://attack.mitre.org/techniques/T1078/004/"
    mitre_attack_version = "v15.1"
    type = "Alert"
    data_source = "OneLogin"
    severity = "Medium"
    priority = "Medium"

  events:
    $login.metadata.event_type = "USER_LOGIN"
    $login.metadata.product_name = "ONELOGIN_SSO"
    $login.metadata.vendor_name = "ONELOGIN"
    $login.security_result.action = "BLOCK"
    $login.metadata.product_event_type = "6" //user failed authentication
    $login.principal.ip = $ip

  match:
    $ip over 1h

  outcome:
    $risk_score = max(35 +
      // Unauthorized target geographies
      if($login.target.ip_geo_artifact.location.country_or_region = "Cuba", 20) +
      if($login.target.ip_geo_artifact.location.country_or_region = "Iran", 20) +
      if($login.target.ip_geo_artifact.location.country_or_region = "North Korea", 20) +
      if($login.target.ip_geo_artifact.location.country_or_region = "Russia", 20) +
      if($login.target.ip_geo_artifact.location.country_or_region = "Syria", 20)
    )
    $mitre_attack_tactic = "Initial Access"
    $mitre_attack_technique = "Valid Accounts: Cloud Accounts"
    $principal_ip = array_distinct($login.principal.ip)
    $principal_ip_country = array_distinct($login.principal.ip_geo_artifact.location.country_or_region)
    $principal_ip_state = array_distinct($login.principal.ip_geo_artifact.location.state)
    $principal_user_userid = array_distinct($login.principal.user.userid)
    $principal_user_user_display_name = array_distinct($login.principal.user.user_display_name)
    $dc_principal_user_userid = count_distinct($login.principal.user.userid)
    $metadata_description = array_distinct($login.metadata.description)

  condition:
    $login and $dc_principal_user_userid > 3
}

Detection logic

Fires when at least one $login event in the 1h window and $dc_principal_user_userid > 3.

Events

$login USER_LOGIN

  • security_result.action = "BLOCK"
  • metadata.product_event_type = "6"

Correlation

Match key
$ip (principal.ip)
Within
1h

Outcome

Fields the detection emits on a match. $risk_score drives alerting; Chronicle surfaces the rest on the detection.

FieldExpression
risk_scoremax(35 + if($login.target.ip_geo_artifact.location.country_or_region = "Cuba", 20) + if($login.target.ip_geo_artifact.location.country_or_region = "Iran", 20) + if($login.target.ip_geo_artifact.location.country_or_region = "North Korea", 20) + if($login.target.ip_geo_artifact.location.country_or_region = "Russia", 20) + if($login.target.ip_geo_artifact.location.country_or_region = "Syria", 20) )
principal_iparray_distinct($login.principal.ip)
principal_ip_countryarray_distinct($login.principal.ip_geo_artifact.location.country_or_region)
principal_ip_statearray_distinct($login.principal.ip_geo_artifact.location.state)
principal_user_useridarray_distinct($login.principal.user.userid)
principal_user_user_display_namearray_distinct($login.principal.user.user_display_name)
dc_principal_user_useridcount_distinct($login.principal.user.userid)
metadata_descriptionarray_distinct($login.metadata.description)