Detects .NET red/black-team tools via name

Hunt Hypothesis

This rule identifies potential adversary activity by detecting known .NET-based Red and Black team tools that are frequently utilized for reconnaissance or post-exploitation tasks within an Azure environment. Proactively hunting for these specific tool names allows the SOC team to distinguish between legitimate security operations and suspicious usage patterns, ensuring early visibility into both authorized testing and unauthorized tool deployment.

YARA Rule

rule HKTL_NET_NAME_NativePayload_IP6DNS {
    meta:
        description = "Detects .NET red/black-team tools via name"
        reference = "https://github.com/DamonMohammadbagher/NativePayload_IP6DNS"
        author = "Arnim Rupp"
        date = "2021-01-22"
    strings:
        $name = "NativePayload_IP6DNS" ascii wide
        $compile = "AssemblyTitle" ascii wide
    condition:
        (uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550) and all of them
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

• Microsoft Defender for Endpoint — Custom indicators / advanced hunting
• Email Gateway — Attachment scanning
• File Share Monitoring — Periodic scanning of shared drives
• YARA CLI — Manual threat hunting on endpoints

This rule contains 2 string patterns in its detection logic.

References

• https://github.com/DamonMohammadbagher/NativePayload_IP6DNS
• Source Rule

False Positive Guidance

Here are 5 specific false positive scenarios for the rule “Detects .NET red/blue-team tools via name,” along with suggested filters or exclusions:

• Scenario: Automated Backup Executions

  • Context: Enterprise backup solutions like Veeam Backup & Replication or Acronis Cyber Protect often utilize .NET-based agents (e.g., Veeam.Backup.Service.exe) that run on a strict schedule. These processes frequently match the naming patterns of security tools because they handle data integrity and reporting, mimicking the behavior of blue-team monitoring agents.
  • Filter/Exclusion: Create an exclusion based on the specific executable path (e.g., C:\Program Files\Veeam\Backup and Replication\...) and restrict the detection to exclude processes running under the dedicated service account (e.g., VeeamServiceAccount or NT SERVICE\Veeam).

• Scenario: CI/CD Pipeline Build Agents

  • Context: In DevOps environments, build agents such as Azure DevOps Agent (Microsoft.TeamFoundation.Build.Agent.exe) or Jenkins running on Windows nodes execute .NET tasks during compilation and deployment. These agents often spawn child processes with names resembling security tooling (e.g., dotnet.exe wrappers) to manage artifacts, triggering the rule during nightly builds.
  • Filter/Exclusion: Exclude process instances where the parent process is a known CI/CD orchestrator (e.g., tfbuild.exe, jenkins-agent.exe) or filter by hostname patterns that identify build servers (e.g., hostnames containing -BUILD- or -AGENT-).

• Scenario: Endpoint Management & Patching Tools

  • Context: Unified endpoint management platforms like Microsoft Intune, SCCM (Configuration Manager), or ManageEngine Desktop Central utilize