Suspicious Windows ANONYMOUS LOGON Local Account Created

SIGMA detection rule by James Pemberton / @4A616D6573 · GPL-2.0

Detects the creation of suspicious accounts similar to ANONYMOUS LOGON, such as using additional spaces. Created as an covering detection for exclusion of Logon Type 3 from ANONYMOUS LOGON accounts.

title: Suspicious Windows ANONYMOUS LOGON Local Account Created
id: e5c627ea-fa27-df99-0573-e47092dc4a98
related:
    - id: 1bbf25b9-8038-4154-a50b-118f2a32be27
      type: derived
status: test
description: Detects the creation of suspicious accounts similar to ANONYMOUS LOGON, such as using additional spaces. Created as an covering detection for exclusion of Logon Type 3 from ANONYMOUS LOGON accounts.
references:
    - https://twitter.com/SBousseaden/status/1189469425482829824
author: James Pemberton / @4A616D6573
date: 2019-10-31
modified: 2022-10-09
tags:
    - attack.persistence
    - attack.t1136.001
    - attack.t1136.002
logsource:
    product: windows
    service: security
detection:
    security:
        Channel: Security
    selection:
        EventID: 4720
        SamAccountName|contains|all:
            - ANONYMOUS
            - LOGON
    condition: security and selection
falsepositives:
    - Unknown
level: high
ruletype: Sigma

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

4724637e-780a-4866-986b-143a69121f41

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

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Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

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[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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