THIS IS A EXPERIMENTAL DETECTION
This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.
The following analytic utilizes Okta's ThreatInsight to identify "Login failures with high unknown users count" and any included secondary outcome reasons. This event will trigger when a brute force attempt occurs with unknown usernames attempted.
- Type: TTP
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2023-03-09
- Author: Okta, Inc, Michael Haag, Splunk
- ID: 632663b0-4562-4aad-abe9-9f621a049738
Kill Chain Phase
- CIS 10
1 2 3 4 5 `okta` eventType="security.threat.detected" AND outcome.reason="Login failures with high unknown users count*" | stats count min(_time) as firstTime max(_time) as lastTime values(displayMessage) by user eventType client.userAgent.rawUserAgent client.userAgent.browser outcome.reason | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `okta_threatinsight_login_failure_with_high_unknown_users_filter`
The SPL above uses the following Macros:
okta_threatinsight_login_failure_with_high_unknown_users_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
How To Implement
This search is specific to Okta and requires Okta logs to be ingested in your Splunk deployment.
Known False Positives
Fidelity of this is high as it is Okta ThreatInsight. Filter and modify as needed.
Associated Analytic Story
|50.0||50||100||Okta ThreatInsight has detected or prevented a high number of login failures.|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 1