Detection: Windows Drivers Loaded by Signature

Description

The following analytic identifies all drivers being loaded on Windows systems using Sysmon EventCode 6 (Driver Load). It leverages fields such as driver path, signature status, and hash to detect potentially suspicious drivers. This activity is significant for a SOC as malicious drivers can be used to gain kernel-level access, bypass security controls, or persist in the environment. If confirmed malicious, this activity could allow an attacker to execute arbitrary code with high privileges, leading to severe system compromise and potential data exfiltration.

1`sysmon` EventCode=6 
2| stats min(_time) as firstTime max(_time) as lastTime values(ImageLoaded) count by dest Signed Signature service_signature_verified service_signature_exists Hashes 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `windows_drivers_loaded_by_signature_filter`

Data Source

Name Platform Sourcetype Source Supported App
Sysmon EventID 6 Windows icon 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($field$)
windows_drivers_loaded_by_signature_filter search *
windows_drivers_loaded_by_signature_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
T1014 Rootkit Defense Evasion
T1068 Exploitation for Privilege Escalation Privilege Escalation
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT28
APT41
Rocke
TeamTNT
Winnti Group
APT28
APT29
APT32
APT33
BITTER
Cobalt Group
FIN6
FIN8
LAPSUS$
MoustachedBouncer
PLATINUM
Scattered Spider
Threat Group-3390
Tonto Team
Turla
Whitefly
ZIRCONIUM

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 process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have the latest version of the Sysmon TA. Most EDR products provide the ability to review driver loads, or module loads, and using a query as such help with hunting for malicious drivers.

Known False Positives

This analytic is meant to assist with identifying drivers loaded in the environment and not to be setup for notables off the bat.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
A driver has loaded on $dest$. 42 60 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 XmlWinEventLog:Microsoft-Windows-Sysmon/Operational xmlwineventlog
Integration ✅ Passing Dataset XmlWinEventLog:Microsoft-Windows-Sysmon/Operational 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: 2