Attempts to Brute Force an Okta User Account

 1[metadata]
 2creation_date = "2020/08/19"
 3integration = ["okta"]
 4maturity = "production"
 5updated_date = "2024/12/09"
 6min_stack_version = "8.15.0"
 7min_stack_comments = "Breaking change at 8.15.0 for the Okta Integration."
 8
 9[rule]
10author = ["Elastic", "@BenB196", "Austin Songer"]
11description = """
12Identifies when an Okta user account is locked out 3 times within a 3 hour window. An adversary may attempt a brute
13force or password spraying attack to obtain unauthorized access to user accounts. The default Okta authentication policy
14ensures that a user account is locked out after 10 failed authentication attempts.
15"""
16from = "now-180m"
17index = ["filebeat-*", "logs-okta*"]
18language = "kuery"
19license = "Elastic License v2"
20name = "Attempts to Brute Force an Okta User Account"
21note = """## Triage and analysis
22
23### Investigating Attempts to Brute Force an Okta User Account
24
25Brute force attacks aim to guess user credentials through exhaustive trial-and-error attempts. In this context, Okta accounts are targeted.
26
27This rule fires when an Okta user account has been locked out 3 times within a 3-hour window. This could indicate an attempted brute force or password spraying attack to gain unauthorized access to the user account. Okta's default authentication policy locks a user account after 10 failed authentication attempts.
28
29#### Possible investigation steps:
30
31- Identify the actor related to the alert by reviewing `okta.actor.alternate_id` field in the alert. This should give the username of the account being targeted.
32- Review the `okta.event_type` field to understand the nature of the events that led to the account lockout.
33- Check the `okta.severity` and `okta.display_message` fields for more context around the lockout events.
34- Look for correlation of events from the same IP address. Multiple lockouts from the same IP address might indicate a single source for the attack.
35- If the IP is not familiar, investigate it. The IP could be a proxy, VPN, Tor node, cloud datacenter, or a legitimate IP turned malicious.
36- Determine if the lockout events occurred during the user's regular activity hours. Unusual timing may indicate malicious activity.
37- Examine the authentication methods used during the lockout events by checking the `okta.authentication_context.credential_type` field.
38
39### False positive analysis:
40
41- Determine whether the account owner or an internal user made repeated mistakes in entering their credentials, leading to the account lockout.
42- Ensure there are no known network or application issues that might cause these events.
43
44### Response and remediation:
45
46- Alert the user and your IT department immediately.
47- If unauthorized access is confirmed, initiate your incident response process.
48- Investigate the source of the attack. If a specific machine or network is compromised, additional steps may need to be taken to address the issue.
49- Require the affected user to change their password.
50- If the attack is ongoing, consider blocking the IP address initiating the brute force attack.
51- Implement account lockout policies to limit the impact of brute force attacks.
52- Encourage users to use complex, unique passwords and consider implementing multi-factor authentication.
53- Check if the compromised account was used to access or alter any sensitive data or systems.
54
55## Setup
56
57The Okta Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule."""
58references = [
59    "https://developer.okta.com/docs/reference/api/system-log/",
60    "https://developer.okta.com/docs/reference/api/event-types/",
61    "https://www.elastic.co/security-labs/testing-okta-visibility-and-detection-dorothy",
62    "https://www.elastic.co/security-labs/monitoring-okta-threats-with-elastic-security",
63    "https://www.elastic.co/security-labs/starter-guide-to-understanding-okta",
64]
65risk_score = 47
66rule_id = "e08ccd49-0380-4b2b-8d71-8000377d6e49"
67severity = "medium"
68tags = ["Use Case: Identity and Access Audit", "Tactic: Credential Access", "Data Source: Okta"]
69timestamp_override = "event.ingested"
70type = "threshold"
71
72query = '''
73event.dataset:okta.system and event.action:user.account.lock
74'''
75
76
77[[rule.threat]]
78framework = "MITRE ATT&CK"
79[[rule.threat.technique]]
80id = "T1110"
81name = "Brute Force"
82reference = "https://attack.mitre.org/techniques/T1110/"
83
84
85[rule.threat.tactic]
86id = "TA0006"
87name = "Credential Access"
88reference = "https://attack.mitre.org/tactics/TA0006/"
89
90[rule.threshold]
91field = ["okta.actor.alternate_id"]
92value = 3