Detection rules › Splunk
Rclone Execution (Windows Event Log)
Rclone is a command line program to manage files on cloud storage. It is a feature rich alternative to cloud vendors' web storage interfaces. Adversaries have been known to use rclone in order to exfiltrate data
MITRE ATT&CK coverage
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
id: '6357.7082'
title: Rclone Execution
description: 'Rclone is a command line program to manage files on cloud storage. It
is a feature rich alternative to cloud vendors'' web storage interfaces. Adversaries
have been known to use rclone in order to exfiltrate data. -- Threat Actor Association:
ALPHV/BlackCat, BlackMatter, DarkSide, Daixin Team, FIN7, FIN8 (Syssphinx), Hello
Kitty / Five Hands, Karakurt, LockBit, Scattered Spider (aka. 0ktapus, UNC3944),
Turla (akaSecret Blizzard, KRYPTON, and UAC-0003), UNC2628, Wizard Spider - Software
Association: Akira, AvosLocker, BazarLoader, BianLian, Blackbyte, Blackcat/ALPHV,
Black Basta, Conti, Lockbit, Ransom Cartel, Royal, Vice Society'
logic_format: Splunk
logic: ' `get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) ("rclone.exe" OR "rclone32.exe" OR (TERM(serve)
OR TERM(COPY) OR TERM(move) OR TERM(COPYto) OR TERM(moveto))) | table _time, host,
user process, process_*, signature_id, parent_* | bin span=1s | stats values(*)
as * by _time, host | where (match(process, "(?i)\s+(((copy|move|moveto|copyto)\s+.*\S+:\S+\s+.*\S+:\S+)|(serve\s+(dlna|http|docker|ftp|restic|sftp|webdav)))")
or match(process_name, "(?i)rclone")) and not match(process_name, "(?i)(cmd|powershell).exe")
`hec_collect`'
techniques:
- exfiltration:exfiltration over web service:exfiltration to cloud storage
- exfiltration:data transfer size limits
- exfiltration:exfiltration over alternative protocol:exfiltration over unencrypted
non-c2 protocol
technique_id:
- T1567.002
- T1030
- T1048.003
data_category:
- Windows event logs
- Process command-line parameters
references:
- https://rclone.org/
- https://www.mcafee.com/blogs/other-blogs/mcafee-labs/darkside-ransomware-victims-sold-short/
- https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html
- https://unit42.paloaltonetworks.com/royal-ransomware/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) ("rclone.exe" OR "rclone32.exe" OR (TERM(serve) OR TERM(COPY) OR TERM(move) OR TERM(COPYto) OR TERM(moveto)))
Stage 2: table
| table _time, host, user process, process_*, signature_id, parent_*
Stage 3: bucket
| bin span=1s
Stage 4: stats
| stats values(*) as * by _time, host
Stage 5: where
| where (match(process, "(?i)\s+(((copy|move|moveto|copyto)\s+.*\S+:\S+\s+.*\S+:\S+)|(serve\s+(dlna|http|docker|ftp|restic|sftp|webdav)))") or match(process_name, "(?i)rclone")) and not match(process_name, "(?i)(cmd|powershell).exe") `hec_collect`
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
process_name | match | "(?i)(cmd|powershell).exe" |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
EventCode | eq |
|
process | match |
|
process_name | match |
|
Search terms
Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.
| Stage | Term |
|---|---|
| 1 | TERM |
| 1 | "<EventID>4688<" |
| 1 | "rclone.exe" |
| 1 | "rclone32.exe" |
| 1 | TERM |
| 1 | serve |
| 1 | TERM |
| 1 | COPY |
| 1 | TERM |
| 1 | move |
| 1 | TERM |
| 1 | COPYto |
| 1 | TERM |
| 1 | moveto |