Enable Remote Connection Between Anonymous Computer - AllowAnonymousCallback

Hunt Hypothesis

Detects enabling of the “AllowAnonymousCallback” registry value, which allows a remote connection between computers that do not have a trust relationship.

Detection Rule

Sigma (Original)

title: Enable Remote Connection Between Anonymous Computer - AllowAnonymousCallback
id: 4d431012-2ab5-4db7-a84e-b29809da2172
status: test
description: Detects enabling of the "AllowAnonymousCallback" registry value, which allows a remote connection between computers that do not have a trust relationship.
references:
    - https://learn.microsoft.com/en-us/windows/win32/wmisdk/connecting-to-wmi-remotely-starting-with-vista
author: X__Junior (Nextron Systems)
date: 2023-11-03
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|contains: '\Microsoft\WBEM\CIMOM\AllowAnonymousCallback'
        Details: 'DWORD (0x00000001)'
    condition: selection
falsepositives:
    - Administrative activity
level: medium

KQL (Azure Sentinel)

imRegistry
| where RegistryKey contains "\\Microsoft\\WBEM\\CIMOM\\AllowAnonymousCallback" and RegistryValueData =~ "DWORD (0x00000001)"

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where RegistryKey contains "\\Microsoft\\WBEM\\CIMOM\\AllowAnonymousCallback" and RegistryValueData =~ "DWORD (0x00000001)"

Required Data Sources

False Positive Guidance

• Administrative activity

MITRE ATT&CK Context

• Technique: T1685 — T1685

References

• https://learn.microsoft.com/en-us/windows/win32/wmisdk/connecting-to-wmi-remotely-starting-with-vista
• SigmaHQ Rule