Detection: Windows WMIC Shadowcopy Delete

Description

This analytic detects the use of WMIC to delete volume shadow copies, which is a common technique used by ransomware actors to prevent system recovery. Ransomware like Cactus often delete shadow copies before encrypting files to ensure victims cannot recover their data without paying the ransom. This behavior is particularly concerning as it indicates potential ransomware activity or malicious actors attempting to prevent system recovery.

 1
 2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=wmic.exe Processes.process = "*shadowcopy*" Processes.process = "*delete*" by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
 3Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
 4Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
 5Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
 6Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product 
 7| `drop_dm_object_name(Processes)` 
 8| `security_content_ctime(firstTime)` 
 9| `security_content_ctime(lastTime)` 
10| `windows_wmic_shadowcopy_delete_filter`

Data Source

Name Platform Sourcetype Source
Sysmon EventID 1 Windows icon Windows 'xmlwineventlog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
windows_wmic_shadowcopy_delete_filter search *
windows_wmic_shadowcopy_delete_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
T1490 Inhibit System Recovery Impact
Actions on Objectives
DE.AE
CIS 10

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

This detection requires Sysmon logging with Event ID 1 (Process Create) enabled. The logs must be processed using the appropriate Splunk Technology Add-ons and mapped to the Endpoint.Processes data model. Ensure that command-line arguments are being logged and that the appropriate permissions are in place to capture this data.

Known False Positives

Legitimate system maintenance or backup operations may occasionally delete shadow copies. However, this activity should be rare and typically performed through approved administrative tools rather than direct WMIC commands. Tune and modify the search to fit your environment, enable as TTP.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

A WMIC command, $process_name$, was detected attempting to delete volume shadow copies spawned off of $parent_process_name$ on $dest$. This is a common ransomware technique used to prevent system recovery.

Risk Object Risk Object Type Risk Score Threat Objects
dest system 10 process_name, parent_process_name

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Passing N/A N/A N/A
Unit Passing Dataset XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Integration ✅ Passing Dataset XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational

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