Potential Signing Bypass Via Windows Developer Features

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

Detects when a user enable developer features such as "Developer Mode" or "Application Sideloading". Which allows the user to install untrusted packages.

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	No specific technique

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: Potential Signing Bypass Via Windows Developer Features
id: a383dec4-deec-4e6e-913b-ed9249670848
related:
    - id: b110ebaf-697f-4da1-afd5-b536fa27a2c1
      type: similar
status: test
description: Detects when a user enable developer features such as "Developer Mode" or "Application Sideloading". Which allows the user to install untrusted packages.
references:
    - Internal Research
    - https://www.sentinelone.com/labs/inside-malicious-windows-apps-for-malware-deployment/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-11
tags:
    - attack.stealth
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith: '\SystemSettingsAdminFlows.exe'
        - OriginalFileName: 'SystemSettingsAdminFlows.EXE'
    selection_flag:
        CommandLine|contains: 'TurnOnDeveloperFeatures'
    selection_options:
        CommandLine|contains:
            - 'DeveloperUnlock'
            - 'EnableSideloading'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith: '\SystemSettingsAdminFlows.exe'
    - OriginalFileName: 'SystemSettingsAdminFlows.EXE'

Stage 2: `selection_flag`

selection_flag:
    CommandLine|contains: 'TurnOnDeveloperFeatures'

Stage 3: `selection_options`

selection_options:
    CommandLine|contains:
        - 'DeveloperUnlock'
        - 'EnableSideloading'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`DeveloperUnlock` `EnableSideloading` `TurnOnDeveloperFeatures`	`field:"CommandLine" kind:match`
`Image`	ends_with	`\SystemSettingsAdminFlows.exe` corpus 2 (sigma 2)	`field:"Image" kind:ends_with value:"\SystemSettingsAdminFlows.exe"`
`OriginalFileName`	eq	`SystemSettingsAdminFlows.EXE` corpus 2 (sigma 2)	`field:"OriginalFileName" kind:eq value:"SystemSettingsAdminFlows.EXE"`