Detection rules › Sigma
RDP Connection Allowed Via Netsh.EXE
Detects usage of the netsh command to open and allow connections to port 3389 (RDP). As seen used by Sarwent Malware
Known false positives
- Legitimate administration activity
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
Rule body
title: RDP Connection Allowed Via Netsh.EXE
id: 01aeb693-138d-49d2-9403-c4f52d7d3d62
status: test
description: Detects usage of the netsh command to open and allow connections to port 3389 (RDP). As seen used by Sarwent Malware
references:
- https://labs.sentinelone.com/sarwent-malware-updates-command-detonation/
author: Sander Wiebing
date: 2020-05-23
modified: 2023-12-11
tags:
- attack.defense-impairment
- attack.t1686.003
logsource:
category: process_creation
product: windows
detection:
selection_img:
- Image|endswith: '\netsh.exe'
- OriginalFileName: 'netsh.exe'
selection_cli:
# Example:
# Old: netsh firewall add portopening TCP 3389 "Open Port 3389"
# New: netsh advfirewall firewall add rule name= "Open Port 3389" dir=in action=allow protocol=TCP localport=3389
CommandLine|contains|all:
- 'firewall '
- 'add '
- 'tcp '
- '3389'
CommandLine|contains:
- 'portopening'
- 'allow'
condition: all of selection_*
falsepositives:
- Legitimate administration activity
level: high
Stages and Predicates
Stage 0: condition
all of selection_*Stage 1: selection_img
selection_img:
- Image|endswith: '\netsh.exe'
- OriginalFileName: 'netsh.exe'
Stage 2: selection_cli
selection_cli:
CommandLine|contains|all:
- 'firewall '
- 'add '
- 'tcp '
- '3389'
CommandLine|contains:
- 'portopening'
- 'allow'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match |
Image | ends_with |
| field:"Image" kind:ends_with value:"\netsh.exe" |
OriginalFileName | eq |
| field:"OriginalFileName" kind:eq value:"netsh.exe" |