MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | T1078 Valid Accounts |
| Persistence | T1078 Valid Accounts |
| Privilege Escalation | T1078 Valid Accounts |
| Stealth | T1078 Valid Accounts |
References
Rule body yaral
/*
* Copyright 2023 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 okta_user_login_out_of_hours {
meta:
author = "Google Cloud Security"
description = "Detects out of hours successful authentication."
rule_id = "mr_36840037-a41c-47d0-b0eb-4096f28855e1"
rule_name = "Okta User Login Out Of Hours"
reference = "https://support.okta.com/help/s/article/User-Signin-and-Recovery-Events-in-the-Okta-System-Log"
mitre_attack_tactic = "Defense Evasion, Persistence, Privilege Escalation, Initial Access"
mitre_attack_technique = "Valid Accounts"
mitre_attack_url = "https://attack.mitre.org/techniques/T1078/"
mitre_attack_version = "v13.1"
type = "Alert"
data_source = "Okta"
severity = "Low"
priority = "Low"
events:
$login.metadata.product_name = "Okta"
$login.metadata.vendor_name = "Okta"
$login.metadata.event_type = "USER_LOGIN"
$login.target.user.email_addresses = $user
$login.security_result.action = "ALLOW"
$login.metadata.event_timestamp.seconds = $timestamp
(
01 = timestamp.get_day_of_week($timestamp, "UTC") or //Sunday
07 = timestamp.get_day_of_week($timestamp, "UTC") //Saturday
)
match:
$user over 1h
outcome:
$risk_score = max(
if (01 = timestamp.get_day_of_week($timestamp, "UTC"), 10) +
if (07 = timestamp.get_day_of_week($timestamp, "UTC"), 15) +
if ( ( timestamp.get_hour($timestamp, "UTC") >= 0 and timestamp.get_hour($timestamp,"UTC")<= 7) or timestamp.get_hour($timestamp,"UTC") > 20, 50)
)
$mitre_attack_tactic = "Defense Evasion, Persistence, Privilege Escalation, Initial Access"
$mitre_attack_technique = "Valid 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)
$principal_ip_city = array_distinct($login.principal.location.city)
$security_result_summary = array_distinct($login.security_result.summary)
$principal_user_managers_email_addresses = array_distinct($login.principal.user.managers.email_addresses)
$principal_user_userid = array_distinct($login.principal.user.userid)
$dc_principal_user_userid = count_distinct($login.principal.user.userid)
$target_user_email_addresses = array_distinct($login.target.user.email_addresses)
$target_user_userid = array_distinct($login.target.user.userid)
$target_user_agent = array_distinct($login.network.http.user_agent)
$security_result_description = array_distinct($login.security_result.description)
condition:
$login
}
Detection logic
Fires when at least one $login event in the 1h window.
Events
$login
security_result.action = "ALLOW"
Correlation
Outcome
Fields the detection emits on a match. $risk_score drives alerting; Chronicle surfaces the rest on the detection.
| Field | Expression |
|---|---|
risk_score | max( if (01 = timestamp.get_day_of_week($timestamp, "UTC"), 10) + if (07 = timestamp.get_day_of_week($timestamp, "UTC"), 15) + if ( ( timestamp.get_hour($timestamp, "UTC") >= 0 and timestamp.get_hour($timestamp,"UTC")<= 7) or timestamp.get_hour($timestamp,"UTC") > 20, 50) ) |
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($login.principal.ip_geo_artifact.location.state) |
principal_ip_city | array_distinct($login.principal.location.city) |
security_result_summary | array_distinct($login.security_result.summary) |
principal_user_managers_email_addresses | array_distinct($login.principal.user.managers.email_addresses) |
principal_user_userid | array_distinct($login.principal.user.userid) |
dc_principal_user_userid | count_distinct($login.principal.user.userid) |
target_user_email_addresses | array_distinct($login.target.user.email_addresses) |
target_user_userid | array_distinct($login.target.user.userid) |
target_user_agent | array_distinct($login.network.http.user_agent) |
security_result_description | array_distinct($login.security_result.description) |