If you are auditing your network to prevent attacks, ensure your mail servers implement the following defenses:
For administrators verifying their own domain infrastructure, web-based tools provide safe, non-intrusive checking mechanisms. Services like MXToolbox or Internet.nl analyze mail server banners, check for open relays, and verify that SPF, DKIM, and DMARC records are correctly aligned. Securing Modern SMTP Environments
These newer tools reflect the evolution of network scanning from simple port checkers to sophisticated, automated security assessment platforms.
HScan 1.2 is a graphical user interface (GUI) tool designed to scan large ranges of IP addresses for open ports and specific service vulnerabilities. Its SMTP scanning module specifically probes mail servers on port 25 to check for: Smtp Scanner Hscan 1.2 Download
Nmap is the gold standard for network discovery and vulnerability scanning. It includes the Nmap Scripting Engine (NSE), which features specific scripts for SMTP auditing. nmap -p 25,465,587 Use code with caution. To run specialized SMTP enumeration scripts:
While Hscan 1.2 is a specialized tool, there are modern alternatives designed for similar tasks, including:
: Configure your mail server to only accept and forward messages from authenticated users or trusted internal IP addresses. If you are auditing your network to prevent
: Once the scan is complete, you will be presented with the results, showing which servers are open relays and may require further action.
It is critical to remember that scanning networks or mail servers that you do not own or have explicit permission to test is illegal in most jurisdictions. Tools like Hscan should only be used in controlled, authorized environments, such as a private lab or during a professional penetration test with a signed Rules of Engagement (RoE) document.
Moreover, responsible disclosure matters. If you discover an open relay, the correct action is to notify the system owner via a responsible channel, not exploit it. Many organizations have bug bounty programs or security contact addresses for this purpose. HScan 1
Hscan 1.2 was designed for legacy operating systems (such as Windows 98, Windows NT, or early Linux kernels). Attempting to run this 32-bit or 16-bit command-line application on modern Windows 10/11 or modern Linux distributions often results in runtime errors, broken dependencies, or crash loops, rendering the download useless. Modern Alternatives for SMTP Auditing
: Scanners check common SMTP ports such as 25 (standard), 587 (TLS), and 465 (SSL).