Detection: Okta ThreatInsight Suspected PasswordSpray Attack

DEPRECATED DETECTION

This detection has been marked as deprecated by the Splunk Threat Research team. This means that it will no longer be maintained or supported. If you have any questions or concerns, please reach out to us at research@splunk.com.

Description

DEPRECATION NOTE - This search has been deprecated and replaced with Okta ThreatInsight Threat Detected. The following analytic utilizes Oktas ThreatInsight to identify "PasswordSpray" and any included secondary outcome reasons. This event will trigger when a brute force attempt occurs with unknown usernames attempted.

1`okta` eventType="security.threat.detected" AND outcome.reason="Password Spray" 
2| stats count min(_time) as firstTime max(_time) as lastTime values(displayMessage) by eventType client.userAgent.rawUserAgent client.userAgent.browser outcome.reason 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `okta_threatinsight_suspected_passwordspray_attack_filter`

Data Source

Name Platform Sourcetype Source Supported App
N/A N/A N/A N/A N/A

Macros Used

Name Value
okta eventtype=okta_log OR sourcetype = "OktaIM2:log"
okta_threatinsight_suspected_passwordspray_attack_filter search *
okta_threatinsight_suspected_passwordspray_attack_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1078 Valid Accounts Defense Evasion
T1078.001 Default Accounts Initial Access
T1110.003 Password Spraying Persistence
KillChainPhase.DELIVERY
KillChainPhase.EXPLOITAITON
KillChainPhase.INSTALLATION
NistCategory.DE_CM
Cis18Value.CIS_10
APT18
APT28
APT29
APT33
APT39
APT41
Akira
Axiom
Carbanak
Chimera
Cinnamon Tempest
Dragonfly
FIN10
FIN4
FIN5
FIN6
FIN7
FIN8
Fox Kitten
GALLIUM
Ke3chang
LAPSUS$
Lazarus Group
Leviathan
OilRig
POLONIUM
PittyTiger
Sandworm Team
Silence
Silent Librarian
Suckfly
Threat Group-3390
Wizard Spider
menuPass
FIN13
Magic Hound
APT28
APT29
APT33
Chimera
HEXANE
Lazarus Group
Leafminer
Silent Librarian

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule 0 * * * *
Earliest Time -70m@m
Latest Time -10m@m
Schedule Window auto
Creates Notable Yes
Rule Title %name%
Rule Description %description%
Notable Event Fields user, dest
Creates Risk Event True
This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

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

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Okta ThreatInsight has detected or prevented a PasswordSpray attack. 60 60 100
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Not Applicable N/A N/A N/A
Unit ❌ Failing N/A N/A N/A
Integration ❌ Failing N/A N/A N/A

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range


Source: GitHub | Version: 2