Detection rules › Sigma
Shell32 DLL Execution in Suspicious Directory
Detects shell32.dll executing a DLL in a suspicious directory
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1218.011 System Binary Proxy Execution: Rundll32 |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
Rule body yaml
title: Shell32 DLL Execution in Suspicious Directory
id: 32b96012-7892-429e-b26c-ac2bf46066ff
status: test
description: Detects shell32.dll executing a DLL in a suspicious directory
references:
- https://www.group-ib.com/resources/threat-research/red-curl-2.html
author: Christian Burkard (Nextron Systems)
date: 2021-11-24
modified: 2023-02-09
tags:
- attack.execution
- attack.stealth
- attack.t1218.011
logsource:
category: process_creation
product: windows
detection:
selection_img:
- Image|endswith: '\rundll32.exe'
- OriginalFileName: 'RUNDLL32.EXE'
selection_cli:
CommandLine|contains|all:
- 'shell32.dll'
- 'Control_RunDLL'
CommandLine|contains:
- '%AppData%'
- '%LocalAppData%'
- '%Temp%'
- '%tmp%'
- '\AppData\'
- '\Temp\'
- '\Users\Public\'
condition: all of selection_*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
all of selection_*Stage 1: selection_img
selection_img:
- Image|endswith: '\rundll32.exe'
- OriginalFileName: 'RUNDLL32.EXE'
Stage 2: selection_cli
selection_cli:
CommandLine|contains|all:
- 'shell32.dll'
- 'Control_RunDLL'
CommandLine|contains:
- '%AppData%'
- '%LocalAppData%'
- '%Temp%'
- '%tmp%'
- '\AppData\'
- '\Temp\'
- '\Users\Public\'
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 |
|---|---|---|
CommandLine | match |
|
Image | ends_with |
|
OriginalFileName | eq |
|