ClickOnce Trust Prompt Tampering

title: ClickOnce Trust Prompt Tampering
id: ac9159cc-c364-4304-8f0a-d63fc1a0aabb
status: test
description: Detects changes to the ClickOnce trust prompt registry key in order to enable an installation from different locations such as the Internet.
references:
    - https://posts.specterops.io/less-smartscreen-more-caffeine-ab-using-clickonce-for-trusted-code-execution-1446ea8051c5
    - https://learn.microsoft.com/en-us/visualstudio/deployment/how-to-configure-the-clickonce-trust-prompt-behavior
author: '@SerkinValery, Nasreddine Bencherchali (Nextron Systems)'
date: 2023-06-12
modified: 2023-08-17
tags:
    - attack.persistence
    - attack.defense-impairment
    - attack.t1112
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains: '\SOFTWARE\MICROSOFT\.NETFramework\Security\TrustManager\PromptingLevel\'
        TargetObject|endswith:
            - '\Internet'
            - '\LocalIntranet'
            - '\MyComputer'
            - '\TrustedSites'
            - '\UntrustedSites'
        Details: 'Enabled'
    condition: selection
falsepositives:
    - Legitimate internal requirements.
level: medium