Identifies when an Okta user account is locked out 3 times within a 3 hour window. An adversary may attempt a brute force or password spraying attack to obtain unauthorized access to user accounts. The default Okta authentication policy ensures that a user account is locked out after 10 failed authentication attempts.
Rule type: threshold
Risk score: 47
Runs every: 5m
Maximum alerts per execution: 100
- Use Case: Identity and Access Audit
- Tactic: Credential Access
- Data Source: Okta
- Austin Songer
Rule license: Elastic License v2
## Triage and analysis ### Investigating Attempts to Brute Force an Okta User Account Brute force attacks aim to guess user credentials through exhaustive trial-and-error attempts. In this context, Okta accounts are targeted. This 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. #### Possible investigation steps: - 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. - Review the `okta.event_type` field to understand the nature of the events that led to the account lockout. - Check the `okta.severity` and `okta.display_message` fields for more context around the lockout events. - 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. - 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. - Determine if the lockout events occurred during the user's regular activity hours. Unusual timing may indicate malicious activity. - Examine the authentication methods used during the lockout events by checking the `okta.authentication_context.credential_type` field. ### False positive analysis: - Determine whether the account owner or an internal user made repeated mistakes in entering their credentials, leading to the account lockout. - Ensure there are no known network or application issues that might cause these events. ### Response and remediation: - Alert the user and your IT department immediately. - If unauthorized access is confirmed, initiate your incident response process. - 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. - Require the affected user to change their password. - If the attack is ongoing, consider blocking the IP address initiating the brute force attack. - Implement account lockout policies to limit the impact of brute force attacks. - Encourage users to use complex, unique passwords and consider implementing multi-factor authentication. - Check if the compromised account was used to access or alter any sensitive data or systems.