The following analytic identifies DCRat delay time tactics using w32tm. This technique was seen in DCRAT malware where it uses stripchart function of w32tm.exe application to delay the execution of its payload like c2 communication , beaconing and execution. This anomaly detection may help the analyst to check other possible event like the process who execute this command that may lead to DCRat attack.
- Type: Anomaly
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-07-28
- Author: Teoderick Contreras, Splunk
- ID: b2cc69e7-11ba-42dc-a269-59c069a48870
Kill Chain Phase
- CIS 3
- CIS 5
- CIS 16
1 2 3 4 5 6 | tstats `security_content_summariesonly` values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name = w32tm.exe Processes.process= "* /stripchart *" Processes.process= "* /computer:localhost *" Processes.process= "* /period:*" Processes.process= "* /dataonly *" Processes.process= "* /samples:*" by Processes.parent_process Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id Processes.dest Processes.user | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_system_time_discovery_w32tm_delay_filter`
The SPL above uses the following Macros:
windows_system_time_discovery_w32tm_delay_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
How To Implement
To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the
Endpoint datamodel in the
Processes node. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.
Known False Positives
Associated Analytic Story
|36.0||60||60||Process name w32tm.exe is using suspcicious command line arguments $process$ on host $dest$.|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 1