Windows reg.exe deletes service registry keys using the delete flag

ATT&CK techniques

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags process creation where reg.exe is executed with a delete action in the context of the services registry path (\SYSTEM\CurrentControlSet\services\). Deleting service registry keys can be used to hinder or remove security-relevant services, supporting defense impairment. It relies on Windows process creation telemetry, matching reg.exe by filename and identifying deletion intent and registry target via command-line substrings.

Reporting behind it

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Windows reg.exe deletes service registry keys using the delete flag

Pivot detection · T1685 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

windows-reg-exe-deletes-service-registry-keys-using-the-delete-flag-05b2aa93

title: Windows reg.exe deletes service registry keys using the delete flag
id: 21a67282-e053-4a1a-98e7-30d3b56e37d4
status: test
description: This rule flags process creation where reg.exe is executed with a delete action in the context of the services registry path (\SYSTEM\CurrentControlSet\services\). Deleting service registry keys can be used to hinder or remove security-relevant services, supporting defense impairment. It relies on Windows process creation telemetry, matching reg.exe by filename and identifying deletion intent and registry target via command-line substrings.
references:
  - https://www.virustotal.com/gui/file/2bcd5702a7565952c44075ac6fb946c7780526640d1264f692c7664c02c68465
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_reg_delete_services.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2022-08-01
modified: 2023-02-04
tags:
  - attack.defense-impairment
  - attack.t1685
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    - Image|endswith: reg.exe
    - OriginalFileName: reg.exe
  selection_delete:
    CommandLine|contains: " delete "
  selection_key:
    CommandLine|contains: \SYSTEM\CurrentControlSet\services\
  condition: all of selection_*
falsepositives:
  - Unlikely
level: high
license: DRL-1.1
related:
  - id: 05b2aa93-1210-42c8-8d9a-2fcc13b284f5
    type: derived

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