Detection: Suspicious writes to System Volume Information

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.

Updated Date: 2024-08-15 ID: cd6297cd-2bdd-4aa1-84aa-5d2f84228fac Author: Rico Valdez, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

This search detects writes to the 'System Volume Information' folder by something other than the System process.

Search

1(`sysmon` OR tag=process) EventCode=11 process_id!=4 file_path=*System\ Volume Information* 
2| stats count min(_time) as firstTime max(_time) as lastTime by dest, Image, file_path 
3| `security_content_ctime(firstTime)`
4| `security_content_ctime(lastTime)` 
5| `suspicious_writes_to_system_volume_information_filter`

Data Source

Name	Platform	Sourcetype	Source	Supported App
Sysmon EventID 1	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`	N/A

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
suspicious_writes_to_system_volume_information_filter	`search *`

suspicious_writes_to_system_volume_information_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
T1036	Masquerading	Defense Evasion

KillChainPhase.EXPLOITAITON

NistCategory.DE_AE

Cis18Value.CIS_10

APT28

APT32

BRONZE BUTLER

Dragonfly

FIN13

LazyScripter

Nomadic Octopus

OilRig

PLATINUM

Sandworm Team

TA551

TeamTNT

Windshift

ZIRCONIUM

menuPass

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

You need to be ingesting logs with both the process name and command-line from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.

Known False Positives

It is possible that other utilities or system processes may legitimately write to this folder. Investigate and modify the search to include exceptions as appropriate.

Associated Analytic Story

Collection and Staging

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
tbd	25	50	50

The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

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: 3