Detection: Crowdstrike Privilege Escalation For Non-Admin User

Updated Date: 2024-07-15 ID: 69e2860c-0e4b-40ae-9dc4-bf9e3bf2a548 Author: Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects CrowdStrike alerts for privilege escalation attempts by non-admin users. These alerts indicate unauthorized efforts by regular users to gain elevated permissions, posing a significant security risk. Detecting and addressing these attempts promptly helps prevent potential breaches and ensures that user privileges remain properly managed, maintaining the integrity of the organization's security protocols.

1`crowdstrike_stream` tag=alert 
2| rename event.EndpointIp as src_ip, event.EndpointName as src_host, event.UserName as user, event.IncidentDescription as description, event.IncidentType as type, event.NumbersOfAlerts as count_alerts, event.SeverityName as severity 
3| stats count min(_time) as firstTime max(_time) as lastTime by src_ip, src_host, user, description, type, count_alerts, severity 
4| where LIKE(type,"%Privilege escalation%") AND NOT LIKE(user, "%adm%") AND NOT LIKE(user, "%svc%") AND NOT LIKE(user, "%admin%") 
5| `security_content_ctime(firstTime)` 
6| `security_content_ctime(lastTime)` 
7| `crowdstrike_privilege_escalation_for_non_admin_user_filter`

Data Source

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

Macros Used

Name Value
crowdstrike_stream sourcetype="CrowdStrike:Event:Streams:JSON"
crowdstrike_privilege_escalation_for_non_admin_user_filter search *
crowdstrike_privilege_escalation_for_non_admin_user_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
T1110 Brute Force Credential Access
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT28
APT38
APT39
DarkVishnya
Dragonfly
FIN5
Fox Kitten
HEXANE
OilRig
Turla

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 Risk Event True
This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To implement CrowdStrike stream JSON logs, use the Falcon Streaming API. Set up an API client, authenticate with your CrowdStrike credentials, and subscribe to the "CrowdStrike:Event:Streams:JSON" event stream. Process and store the JSON logs as needed, integrating them into your logging or SIEM system for monitoring and analysis.

Known False Positives

unknown

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
A Privilege escalation happened in Non-Admin Account in $src_host$ 49 70 70
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 ✅ Passing N/A N/A N/A
Unit ✅ Passing Dataset CrowdStrike:Event:Streams CrowdStrike:Event:Streams:JSON
Integration ✅ Passing Dataset CrowdStrike:Event:Streams CrowdStrike:Event:Streams:JSON

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: 1