Detection rules › Sigma
NTFS symbolic link configuration change
Detects scenarios where an attacker attempts to modify the type of symbolic link than can be created.
Known false positives
- admin activity on file server
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
title: NTFS symbolic link configuration change
description: Detects scenarios where an attacker attempts to modify the type of symbolic link than can be created.
references:
- https://news.sophos.com/en-us/2022/08/10/lockbit-hive-and-blackcat-attack-automotive-supplier-in-triple-ransomware-attack/
- https://www.microsoft.com/en-us/security/blog/2022/06/13/the-many-lives-of-blackcat-ransomware/
- https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/fsutil-behavior
tags:
- attack.persistence
- attack.t1547.009 # Boot or Logon Autostart Execution: Shortcut Modification
author: mdecrevoisier
status: experimental
logsource:
product: windows
category: process_creation
detection: # 'fsutil behavior set SymlinkEvaluation R2L:1'
selection:
NewProcessName|endswith: '\fsutil.exe'
CommandLine|contains|all:
- behavior
- set
condition: selection
falsepositives:
- admin activity on file server
level: medium
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
NewProcessName|endswith: '\fsutil.exe'
CommandLine|contains|all:
- behavior
- set
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match |
NewProcessName | ends_with |
| field:"Image" kind:ends_with value:"\fsutil.exe" |