The Windows Command Prompt (cmd.exe) is often overshadowed by PowerShell and GUI tools, yet it remains a direct, scriptable interface for network diagnostics, system enumeration, and lightweight security checks. When used on your own devices or in authorized lab environments, these commands form the foundation of ethical reconnaissance — no third-party tools required.
Why CMD Still Matters in Security Testing
Modern penetration testing distributions like Kali Linux offer hundreds of dedicated tools, but the Windows command line is already present on every corporate and personal Windows machine. Knowing how to extract information from it without raising alerts is a skill that translates directly into real-world incident response and system administration. Moreover, many compliance frameworks require administrators to verify network configurations using built-in utilities before deploying specialized scanners.
Essential CMD Commands for Network Reconnaissance
The following commands are safe to run on any system you own or have explicit permission to test. They reveal network topology, active connections, and service states.
| Command | Typical Output | Security Use Case |
|---|---|---|
ipconfig /all |
IP addresses, MAC, DNS servers, DHCP lease info | Identify network segmentation and default gateway |
ping -n 1 <target> |
Round-trip time, TTL | Check host availability and estimate OS via TTL |
tracert <target> |
Hop-by-hop route to destination | Map network paths and locate firewalls |
nslookup <domain> |
IP addresses associated with domain | Verify DNS resolution and detect spoofing |
netstat -an |
All active TCP/UDP connections and listening ports | Discover unexpected services or backdoors |
arp -a |
IP-to-MAC address mapping cache | Detect ARP spoofing or duplicate IPs |
Running these commands from an administrative prompt (Run as administrator) may reveal additional information such as routing tables (route print) and cached DNS entries (ipconfig /displaydns).
System Information Gathering
Before testing a system's resilience, you need to know what you are working with. The following commands enumerate hardware, software, and user details without installing anything.
systeminfo– OS version, hotfixes, boot time, memory, and network adapter details. Useful for identifying missing patches.tasklist /svc– Lists running processes and their associated services. Spot unknown or suspicious processes.wmic os get Caption,CSDVersion– Quick OS version and service pack. WMI can also query disk drives, BIOS, and installed software.net user– Lists local user accounts. Combined withnet localgroup administrators, it reveals privileged accounts.driverquery /v– Lists all device drivers and their signing status. Third-party unsigned drivers are a common attack vector.
All of these commands are standard diagnostic tools used by IT support. In a security context, they help you build a baseline of a clean system so that anomalies stand out during an incident.
Using CMD for Basic Vulnerability Checks
While CMD cannot replace a dedicated vulnerability scanner, it can quickly flag common misconfigurations.
Open Shares
net share displays all shared folders on the local machine. If you see default administrative shares (C$, ADMIN$) that are not needed, consider disabling them. On a remote machine, use net view \target-ip to list shares (requires credentials).
Listening Ports
We already covered netstat -an. Pay special attention to ports like 3389 (RDP), 445 (SMB), and 22 (SSH if using Windows Subsystem for Linux). Unexpected open ports should be investigated.
Weak Password Policies
net accounts shows password policy (minimum length, lockout threshold). A policy that allows short passwords or no lockout is a risk. This is a legitimate check for compliance audits.
Ethical Boundaries and Lab Setup
Every command above is legal to run on your own computer or on a system you have written permission to test. To practice safely, set up a virtual lab using VirtualBox or VMware with a Windows virtual machine as the target and a second Windows VM (or a Linux distribution like Kali) as the attacker. Many ethical hackers prefer dedicated Linux environments for advanced tasks — you can read more about the best operating systems for ethical hackers and pentesters to choose the right platform for your lab.
Before running any network scans, ensure your antivirus is up to date. Even benign CMD commands can trigger false positives if a security tool misinterprets them. The best free antivirus software for Windows 10 often includes network monitoring features that alert you to unusual traffic — use those alerts as learning opportunities rather than disabling them.
Practical Workflow: From CMD to a Simple Security Report
Here is a concrete sequence you can run today on your own Windows machine. Open CMD as administrator and execute the following:
ipconfig /all > network_baseline.txtnetstat -an > connections.txttasklist /svc > processes.txtsysteminfo > system_info.txt
Compare the output of netstat -an against a known baseline (run it again after a clean boot). Any new listening ports or established connections to unfamiliar IPs could indicate malware. Cross‑reference with the processes list to identify the responsible executable. This manual triage is exactly what incident responders do — and you can learn it using nothing but built‑in Windows tools.
Start by running ipconfig /all on your own machine to understand your network interface configuration — then move on to netstat -an to see active connections. Document your findings in a lab notebook. Over time, you will develop an intuition for what is normal and what deserves a closer look.
