DHCP Callout DLL Installation

Hunt Hypothesis

Detects the installation of a Callout DLL via CalloutDlls and CalloutEnabled parameter in Registry, which can be used to execute code in context of the DHCP server (restart required)

Detection Rule

Sigma (Original)

title: DHCP Callout DLL Installation
id: 9d3436ef-9476-4c43-acca-90ce06bdf33a
status: test
description: Detects the installation of a Callout DLL via CalloutDlls and CalloutEnabled parameter in Registry, which can be used to execute code in context of the DHCP server (restart required)
references:
    - https://blog.3or.de/mimilib-dhcp-server-callout-dll-injection.html
    - https://technet.microsoft.com/en-us/library/cc726884(v=ws.10).aspx
    - https://msdn.microsoft.com/de-de/library/windows/desktop/aa363389(v=vs.85).aspx
author: Dimitrios Slamaris
date: 2017-05-15
modified: 2023-08-17
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.stealth
    - attack.defense-impairment
    - attack.t1574.001
    - attack.t1112
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|endswith:
            - '\Services\DHCPServer\Parameters\CalloutDlls'
            - '\Services\DHCPServer\Parameters\CalloutEnabled'
    condition: selection
falsepositives:
    - Unknown
level: high

KQL (Azure Sentinel)

imRegistry
| where RegistryKey endswith "\\Services\\DHCPServer\\Parameters\\CalloutDlls" or RegistryKey endswith "\\Services\\DHCPServer\\Parameters\\CalloutEnabled"

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where RegistryKey endswith "\\Services\\DHCPServer\\Parameters\\CalloutDlls" or RegistryKey endswith "\\Services\\DHCPServer\\Parameters\\CalloutEnabled"

Required Data Sources

False Positive Guidance

• Unknown

MITRE ATT&CK Context

• Tactic: Privilege Escalation
• Tactic: Persistence
• Tactic: Execution
• Technique: T1574.001 — T1574.001
• Technique: T1112 — T1112

References

• https://blog.3or.de/mimilib-dhcp-server-callout-dll-injection.html
• https://technet.microsoft.com/en-us/library/cc726884(v=ws.10).aspx
• https://msdn.microsoft.com/de-de/library/windows/desktop/aa363389(v=vs.85).aspx
• SigmaHQ Rule