Okta Brute Force or Password Spraying Attackedit

Identifies a high number of failed Okta user authentication attempts from a single IP address, which could be indicative of a brute force or password spraying attack. An adversary may attempt a brute force or password spraying attack to obtain unauthorized access to user accounts.

Rule type: threshold

Rule indices:

  • filebeat-*
  • logs-okta*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: None (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Use Case: Identity and Access Audit
  • Tactic: Credential Access
  • Data Source: Okta

Version: 208

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guideedit

Triage and analysis

Investigating Okta Brute Force or Password Spraying Attack

This rule alerts when a high number of failed Okta user authentication attempts occur from a single IP address. This could be indicative of a brute force or password spraying attack, where an adversary may attempt to gain unauthorized access to user accounts by guessing the passwords.

Possible investigation steps:

  • Review the source.ip field to identify the IP address from which the high volume of failed login attempts originated.
  • Look into the event.outcome field to verify that these are indeed failed authentication attempts.
  • Determine the user.name or user.email related to these failed login attempts. If the attempts are spread across multiple accounts, it might indicate a password spraying attack.
  • Check the timeline of the events. Are the failed attempts spread out evenly, or are there burst periods, which might indicate an automated tool?
  • Determine the geographical location of the source IP. Is this location consistent with the user’s typical login location?
  • Analyze any previous successful logins from this IP. Was this IP previously associated with successful logins?

False positive analysis:

  • A single user or automated process that attempts to authenticate using expired or wrong credentials multiple times may trigger a false positive.
  • Analyze the behavior of the source IP. If the IP is associated with legitimate users or services, it may be a false positive.

Response and remediation:

  • If you identify unauthorized access attempts, consider blocking the source IP at the firewall level.
  • Notify the users who are targeted by the attack. Ask them to change their passwords and ensure they use unique, complex passwords.
  • Enhance monitoring on the affected user accounts for any suspicious activity.
  • If the attack is persistent, consider implementing CAPTCHA or account lockouts after a certain number of failed login attempts.
  • If the attack is persistent, consider implementing multi-factor authentication (MFA) for the affected user accounts.
  • Review and update your security policies based on the findings from the incident.

Setupedit

The Okta Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.

Rule queryedit

event.dataset:okta.system and event.category:authentication and event.outcome:failure

Framework: MITRE ATT&CKTM