T1016.001_internet-connection-discovery

T1016.001 Internet Connection Discovery

Sub-technique of: T1016

High-Level Description

Adversaries may check for Internet connectivity on compromised systems. This may be performed during automated discovery and can be accomplished in numerous ways such as using Ping, tracert, and GET requests to websites, or performing initial speed testing to confirm bandwidth.

Adversaries may use the results and responses from these requests to determine if the system is capable of communicating with their C2 servers before attempting to connect to them. The results may also be used to identify routes, redirectors, and proxy servers.

Kill Chain Phase

• Discovery (TA0007)

Platforms: Windows, Linux, macOS, ESXi

What to Check

• Identify if Internet Connection Discovery technique is applicable to target environment
• Check Windows systems for indicators of Internet Connection Discovery
• Check Linux systems for indicators of Internet Connection Discovery
• Check macOS systems for indicators of Internet Connection Discovery
• Assess detection coverage (1 detection strategies)

How to Test

Atomic Red Team Tests

The following tests are from Atomic Red Team and provide actionable ways to test this technique:

Atomic Test 1: Check internet connection using ping Windows

Check internet connection using ping on Windows. The default target of the ping is 8.8.8.8 (Google Public DNS).

Supported Platforms: windows

ping -n 4 #{ping_target}

Atomic Test 2: Check internet connection using ping freebsd, linux or macos

Check internet connection using ping on Linux, MACOS. The default target of the ping is 8.8.8.8 (Google Public DNS).

Supported Platforms: macos, linux

ping -c 4 #{ping_target}

Atomic Test 3: Check internet connection using Test-NetConnection in PowerShell (ICMP-Ping)

Check internet connection using PowerShell's Test-NetConnection cmdlet and the ICMP/Ping protocol. The default target is 8.8.8.8 (Google Public DNS).

Supported Platforms: windows

Test-NetConnection -ComputerName #{target}

Atomic Test 4: Check internet connection using Test-NetConnection in PowerShell (TCP-HTTP)

Check internet connection using PowerShell's Test-NetConnection cmdlet and the TCP protocol to check for outbound HTTP (Port 80) access. The default target is www.google.com.

Supported Platforms: windows

Test-NetConnection -CommonTCPPort HTTP -ComputerName #{target}

Atomic Test 5: Check internet connection using Test-NetConnection in PowerShell (TCP-SMB)

Check internet connection using PowerShell's Test-NetConnection cmdlet and the TCP protocol to check for outbound SMB (Port 445) access. The default target is 8.8.8.8.

Supported Platforms: windows

Test-NetConnection -CommonTCPPort SMB -ComputerName #{target}

Manual Testing

If Atomic Red Team tests are not applicable, manually verify the technique by:

1. Identify Attack Surface: Determine if the target environment is susceptible to Internet Connection Discovery by examining the target platforms (Windows, Linux, macOS).

2. Assess Existing Defenses: Review whether mitigations for T1016.001 are in place. If defenses are absent or misconfigured, this technique may be exploitable.

3. Execute Test: Use tools and methods described in the MITRE ATT&CK page and external references below.

Remediation Guide

No specific mitigations documented for this technique.

Detection

Behavioral Detection of Internet Connection Discovery

Risk Assessment

CWE Categories

References

• Atomic Red Team - T1016.001
• MITRE ATT&CK - T1016.001