NMAP (Network Mapper) is a popular open-source tool used by network administrators and security professionals to discover hosts and services on a computer network. With the increasing incidences of cyber threats, it’s crucial to take measures to counterbalance NMAP scanning, thus mitigating potential security risks.
The most effective way to counteract NMAP scanning is by employing Network Intrusion Detection Systems (NIDS). NIDS is proficient at identifying and disabling NMAP scans. Snort, a well-acknowledged open-source NIDS, is particularly effective in countering such potential threats. Snort rules can be customized to detect a variety of scanning techniques, flagging them, and potentially blocking the source IP address (Roesch, M., 1999).
A method used by many cybersecurity experts to counterbalance an NMAP scanning technique called SYN scanning is by configuring firewalls to deny all incoming SYN packets except those returning from outbound established connections. This process is also known as TCP Intercept or SYN Proxy (Cisco, 2005).
In addition, utilizing rules in the Intrusion Prevention System (IPS) to identify NMAP scans can be beneficial. The IPS can subsequently enforce an action upon detection, like blocking the source IP address. Commercial solutions like TippingPoint and Check Point offer such functionalities (TippingPoint, n.d.; Check Point, n.d.)
Another effective way includes employing the dynamic or static packet filtering technique. By examining the packet data, the routers, and firewalls make informed decisions enhancing network security. According to Cisco (2001), static and dynamic packet filters decide on whether to forward or drop incoming packets based on pre-established rules.
Host-based intrusion prevention systems (HIPS), like Symantec’s Critical System Protection, can also be optimized to mitigate the risk of NMAP scanning. HIPS function by monitoring a single host for suspicious activity (Symantec, n.d.).
Finally, regularly patching and updating system software helps to eliminate vulnerabilities that NMAP could potentially exploit. Software vendors routinely provide patches to counteract new threats, making patching an essential strategy in combating NMAP scanning (Microsoft, n.d.).
In summary, several techniques can be employed to counterbalance NMAP scanning, including using NIDS like Snort, applying TCP Intercept, configuring rules in IPS, using packet filtering techniques, deploying HIPS, and regularly patching and updating system software.
Sources:
1. Cisco (2001). Packet Filtering and Network Security. www.cisco.com
2. Cisco (2005). Understanding TCP Intercept (Protect Your Network). www.cisco.com
3. Roesch, M. (1999). Snort – Lightweight Intrusion Detection for Networks. 13th USENIX conference on System administration – LISA ’99
4. TippingPoint (n.d.). TippingPoint Threat Protection System. www.trendmicro.com
5. Check Point (n.d.). Intrusion Prevention System (IPS). www.checkpoint.com
6. Symantec (n.d.). Host-Based Intrusion Prevention System (HIPS). us.norton.com
7. Microsoft (n.d.). Patch and update management. docs.microsoft.com
