Detect Renamed RClone
Description
The following analytic identifies the usage of rclone.exe
, renamed, being used to exfiltrate data to a remote destination. RClone has been used by multiple ransomware groups to exfiltrate data. In many instances, it will be downloaded from the legitimate site and executed accordingly. During triage, isolate the endpoint and begin to review parallel processes for additional behavior. At this stage, the adversary may have staged data to be exfiltrated.
- Type: Hunting
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2021-09-16
- Author: Michael Haag, Splunk
- ID: 6dca1124-b3ec-11eb-9328-acde48001122
Annotations
Kill Chain Phase
- Exploitation
NIST
CIS20
CVE
Search
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| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.original_file_name=rclone.exe AND Processes.process_name!=rclone.exe) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.original_file_name
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `detect_renamed_rclone_filter`
Macros
The SPL above uses the following Macros:
detect_renamed_rclone_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- _time
- Processes.dest
- Processes.user
- Processes.parent_process_name
- Processes.parent_process
- Processes.original_file_name
- Processes.process_name
- Processes.process
- Processes.process_id
- Processes.parent_process_path
- Processes.process_path
- Processes.parent_process_id
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
False positives should be limited as this analytic identifies renamed instances of rclone.exe
. Filter as needed if there is a legitimate business use case.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
27.0 | 30 | 90 | The following $process_name$ has been identified as renamed, spawning from $parent_process_name$ on $dest$ by $user$. |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://redcanary.com/blog/rclone-mega-extortion/
- https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations
- https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
Test Dataset
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 | version: 2