Detection rules › Sigma
Event log deactivation or size reduction (command)
Detects scenarios where an attacker disable or reduce the size of an event log.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1562.002 Impair Defenses: Disable Windows Event Logging |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
title: Event log deactivation or size reduction (command)
description: Detects scenarios where an attacker disable or reduce the size of an event log.
references:
- https://www.recordedfuture.com/five-common-ransomware-techniques
- https://www.cybereason.com/blog/research/cybereason-vs.-ransomexx-ransomware
- https://research.splunk.com/endpoint/236e7c8e-c9d9-11eb-a824-acde48001122/
tags:
- attack.defense_evasion
- attack.t1562.002 # Disable Windows Event Logging
author: mdecrevoisier
status: experimental
logsource:
product: windows
category: process_creation
detection: # Full command: wevtutil.exe” sl Security /e:false
selection:
NewProcessName|endswith: '\wevtutil.exe'
CommandLine|contains:
- 'set-log'
- sl # reduced command
CommandLine|contains:
- '/e:false' # <Enabled> - Does not work with all channel
- '/ms:' # <MaxSize> - suspicious if low value (min is 64Kb)
condition: selection
falsepositives:
- None
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
NewProcessName|endswith: '\wevtutil.exe'
CommandLine|contains:
- 'set-log'
- sl
CommandLine|contains:
- '/e:false'
- '/ms:'
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 |
|
NewProcessName | ends_with |
|