Detection rules › Sigma

Disable Macro Runtime Scan Scope

Status
test
Severity
high
Log source
category registry_set, product windows
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects tampering with the MacroRuntimeScanScope registry key to disable runtime scanning of enabled macros

MITRE ATT&CK coverage

TacticTechniques
Defense ImpairmentNo specific technique

Telemetry coverage

Rule body

title: Disable Macro Runtime Scan Scope
id: ab871450-37dc-4a3a-997f-6662aa8ae0f1
description: Detects tampering with the MacroRuntimeScanScope registry key to disable runtime scanning of enabled macros
status: test
date: 2022-10-25
modified: 2023-08-17
author: Nasreddine Bencherchali (Nextron Systems)
references:
    - https://www.microsoft.com/en-us/security/blog/2018/09/12/office-vba-amsi-parting-the-veil-on-malicious-macros/
    - https://admx.help/?Category=Office2016&Policy=office16.Office.Microsoft.Policies.Windows::L_MacroRuntimeScanScope
    - https://github.com/S3cur3Th1sSh1t/OffensiveVBA/blob/28cc6a2802d8176195ac19b3c8e9a749009a82a3/src/AMSIbypasses.vba
tags:
    - attack.defense-impairment
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|contains|all:
            - '\SOFTWARE\'
            - '\Microsoft\Office\'
            - '\Common\Security'
        TargetObject|endswith: '\MacroRuntimeScanScope'
        Details: DWORD (0x00000000)
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetObject|contains|all:
        - '\SOFTWARE\'
        - '\Microsoft\Office\'
        - '\Common\Security'
    TargetObject|endswith: '\MacroRuntimeScanScope'
    Details: DWORD (0x00000000)

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Detailseq
  • DWORD (0x00000000) corpus 38 (sigma 36, chronicle 2)
field:"Details" kind:eq value:"DWORD (0x00000000)"
TargetObjectends_with
  • \MacroRuntimeScanScope
field:"TargetObject" kind:ends_with value:"\MacroRuntimeScanScope"
TargetObjectmatch
  • \Common\Security
  • \Microsoft\Office\ corpus 2 (sigma 2)
  • \SOFTWARE\
field:"TargetObject" kind:match