Potential Raspberry Robin CPL Execution Activity

Status: test
Severity: high
Log source: category process_creation, product windows
Author: Swachchhanda Shrawan Poudel
Source: github.com/SigmaHQ/sigma

Detects the execution of a ".CPL" file located in the user temp directory via the Shell32 DLL "Control_RunDLL" export function. This behavior was observed in multiple Raspberry-Robin variants.

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1218.011` System Binary Proxy Execution: Rundll32

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: Potential Raspberry Robin CPL Execution Activity
id: 92020b88-9caf-464f-bad8-cd0fb0aa2a81
status: test
description: |
    Detects the execution of a ".CPL" file located in the user temp directory via the Shell32 DLL "Control_RunDLL" export function.
    This behavior was observed in multiple Raspberry-Robin variants.
references:
    - https://tria.ge/240226-fhbe7sdc39/behavioral1
    - https://bazaar.abuse.ch/browse/signature/RaspberryRobin/
author: Swachchhanda Shrawan Poudel
date: 2024-03-07
tags:
    - attack.execution
    - attack.stealth
    - attack.t1218.011
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    # Example: "C:\Windows\system32\rundll32.exe" Shell32.dll,Control_RunDLL "C:\Users\xxxx\AppData\Local\Temp\xxxx.CPL"
    selection_parent_img:
        ParentImage|endswith:
            - '\rundll32.exe'
            - '\control.exe'
    selection_img:
        - Image|endswith: '\rundll32.exe'
        - OriginalFileName: 'RUNDLL32.EXE'
    selection_cli:
        CommandLine|contains|all:
            - 'shell32.dll'
            - 'Control_RunDLL'
            - '.CPL'
    selection_path:
        CommandLine|contains: '\AppData\Local\Temp\'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_parent_img`

selection_parent_img:
    ParentImage|endswith:
        - '\rundll32.exe'
        - '\control.exe'

Stage 2: `selection_img`

selection_img:
    - Image|endswith: '\rundll32.exe'
    - OriginalFileName: 'RUNDLL32.EXE'

Stage 3: `selection_cli`

selection_cli:
    CommandLine|contains|all:
        - 'shell32.dll'
        - 'Control_RunDLL'
        - '.CPL'

Stage 4: `selection_path`

selection_path:
    CommandLine|contains: '\AppData\Local\Temp\'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`.CPL` corpus 3 (sigma 3) `Control_RunDLL` corpus 6 (sigma 3, splunk 2, elastic 1) `\AppData\Local\Temp\` corpus 28 (sigma 26, elastic 2) `shell32.dll` corpus 3 (sigma 3)	`field:"CommandLine" kind:match`
`Image`	ends_with	`\rundll32.exe` corpus 94 (sigma 94)	`field:"Image" kind:ends_with value:"\rundll32.exe"`
`OriginalFileName`	eq	`RUNDLL32.EXE` corpus 78 (sigma 35, elastic 22, splunk 21)	`field:"OriginalFileName" kind:eq value:"RUNDLL32.EXE"`
`ParentImage`	ends_with	`\control.exe` `\rundll32.exe` corpus 15 (sigma 15)	`field:"ParentImage" kind:ends_with`

Potential Raspberry Robin CPL Execution Activity

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_parent_img

Stage 2: selection_img