Detection rules › Sigma
Certutil payload obfuscation (command)
Detects scenarios where an attacker attempts to abuse certutil command to download obfuscated malicious payload. Tools like Tchopper can trigger this rule.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1140 Deobfuscate/Decode Files or Information |
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: Certutil payload obfuscation (command)
description: Detects scenarios where an attacker attempts to abuse certutil command to download obfuscated malicious payload. Tools like Tchopper can trigger this rule.
references:
- https://www.elastic.co/guide/en/security/current/suspicious-certutil-commands.html
- https://www.bleepingcomputer.com/news/security/certutilexe-could-allow-attackers-to-download-malware-while-bypassing-av/
- https://attack.mitre.org/software/S0160/
- https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/certutil
- https://www.sentinelone.com/blog/malware-living-off-land-with-certutil/
- https://thedfirreport.com/2022/07/11/select-xmrig-from-sqlserver/
tags:
- attack.defense_evasion
- attack.t1140
author: mdecrevoisier
status: experimental
logsource:
product: windows
category: process_creation
detection:
selection:
NewProcessName|endswith: '\certutil.exe'
CommandLine|contains:
#- urlcache # see other related rule
- decode
- encode
- encodehex
- decodehex
condition: selection
falsepositives:
- CSAT Cyber Security Assessment Tool
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
NewProcessName|endswith: '\certutil.exe'
CommandLine|contains:
- decode
- encode
- encodehex
- decodehex
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 |
|