Detection: Windows Event For Service Disabled

Updated Date: 2024-10-17 ID: 9c2620a8-94a1-11ec-b40c-acde48001122 Author: Teoderick Contreras, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic detects when a Windows service is modified from a start type to disabled. It leverages system event logs, specifically EventCode 7040, to identify this change. This activity is significant because adversaries often disable security or other critical services to evade detection and maintain control over a compromised host. If confirmed malicious, this action could allow attackers to bypass security defenses, leading to further exploitation and persistence within the environment.

1`wineventlog_system` EventCode=7040  EventData_Xml="*disabled*" 
2| stats count min(_time) as firstTime max(_time) as lastTime by Computer EventCode Name UserID service ServiceName 
3| rename Computer as dest 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_event_for_service_disabled_filter`

Data Source

Name Platform Sourcetype Source
Windows Event Log System 7040 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:System'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_event_for_service_disabled_filter search *
windows_event_for_service_disabled_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
T1562.001 Disable or Modify Tools Defense Evasion
T1562 Impair Defenses Defense Evasion
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
Agrius
Aquatic Panda
BRONZE BUTLER
Ember Bear
FIN6
Gamaredon Group
Gorgon Group
INC Ransom
Indrik Spider
Kimsuky
Lazarus Group
Magic Hound
MuddyWater
Play
Putter Panda
Rocke
Saint Bear
TA2541
TA505
TeamTNT
Turla
Wizard Spider
Magic Hound

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 False
This configuration file applies to all detections of type hunting.

Implementation

To successfully implement this search, you need to be ingesting logs with the Service name, Service File Name Service Start type, and Service Type from your endpoints.

Known False Positives

Windows service update may cause this event. In that scenario, filtering is needed.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Service $ServiceName$ was disabled on $dest$ 36 60 60
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 XmlWinEventLog:System XmlWinEventLog
Integration ✅ Passing Dataset XmlWinEventLog:System XmlWinEventLog

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: 5