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

Tactic	Techniques
Initial Access	`T1078.004` Valid Accounts: Cloud Accounts

Rule body

// Copyright 2024 Google LLC. Licensed under Apache-2.0.

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
}

YARA-L rule structure

Condition

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"

Match and correlation

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

Outcome

Outcome variables add context to a detection. When the rule generates an alert, $risk_score is displayed with it.

Field	Expression
`risk_score`	`max(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($login.target.ip_geo_artifact.location.country_or_region = "Syria", 20) )`
`principal_ip`	`array_distinct($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)`