Enable Remote Connection Between Anonymous Computer - AllowAnonymousCallback

Status: test
Severity: medium
Log source: category registry_set, product windows
Author: X__Junior (Nextron Systems)
Source: github.com/SigmaHQ/sigma

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

Known false positives

Administrative activity

MITRE ATT&CK coverage

Tactic	Techniques
Defense Impairment	`T1685` Disable or Modify Tools

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 13: RegistryEvent (Value Set)

Rule body

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

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    TargetObject|contains: '\Microsoft\WBEM\CIMOM\AllowAnonymousCallback'
    Details: 'DWORD (0x00000001)'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Details`	eq	`DWORD (0x00000001)` corpus 40 (sigma 36, chronicle 4)	`field:"Details" kind:eq value:"DWORD (0x00000001)"`
`TargetObject`	match	`\Microsoft\WBEM\CIMOM\AllowAnonymousCallback`	`field:"TargetObject" kind:match value:"\Microsoft\WBEM\CIMOM\AllowAnonymousCallback"`