Enable the NIDS mode of snort as done above. So if you want to scan any other port then replace 22 from the port you want to scan else you can also use “any” to analysis all ports. alert tcp any any -> 192.168.1.105 22 (msg:"Nmap XMAS Tree Scan" flags:FPU sid:1000006 rev:1 )Īgain above rule is only applicable for port 22 which will listen for incoming traffic when packets come from Fin, PSH & URG flags. Let assume attacker may choose XMAS scanning for network enumeration then in that situation we can apply the following rule in snort local rule file. Hence you can block this IP to protect your network from further scanning.Īs we know that TCP communication follows three-way handshake to established TCP connection with target machine but sometimes instead of using SYN, SYN/ACK, ACK flag attacker choose XMAS scan to connect with the target by sending data packets through Fin, PSH & URG flags.
![zenmap port scan zenmap port scan](https://hackertarget.com/wp-content/uploads/2019/02/schedule-nmap-port-scans.png)
Here you can confirm that our snort is absolutely working when the attacker is scanning port 22 using nmap TCP scan and it is showing attacker’s IP from where traffic is coming on port 22. Now again using the attacker machine execute the given below command for TCP scan on port 22.
![zenmap port scan zenmap port scan](https://phoenixnap.com/kb/wp-content/uploads/2021/04/nmap-open-ports-1.png)
alert tcp any any -> 192.168.1.105 22 (msg: "NMAP TCP Scan" sid:10000005 rev:2 )Ībove rule is only applicable for port 22 so if you want to scan any other port then replace 22 from the port you want to scan or else you can also use “any” to analysis all ports. Let’s assume attacker may choose TCP scanning for network enumeration then in that situation we can apply the following rule in snort local rule file. Now in order to connect with the target network, an attacker may go for networking enumeration either using TCP Protocol or UDP protocol. sudo snort -A console -q -u snort -g snort -c /etc/snort/nf -i eth0 Hence, you can block the attacker’s IP to protect your network from further scanning. Here, you will observe that it is generating an alert for NMAP Ping Sweep scan. These both are parts of network traffic.Ĭome back to over your target machine where snort is capturing all in-coming traffic. Hence in given below image, you can notice ICMP request packet along with ICMP reply packets. If you will execute above command without parameter “disable arp-ping” then will work as default ping sweep scan which will send arp packets in spite of sending ICMP on targets network and maybe snort not able to capture NMAP Ping scan in that scenario, therefore we had use parameter “disable arp-ping” in the above command.Īs I had declaimed above why we are involving Wireshark in this tutorial so that you can clearly see the packet sends form attacker network to targets network. Now using attacking machine execute given below command to identify the status of the target machine i.e. Turn on IDS mode of snort by executing given below command in terminal: sudo snort -A console -q -u snort -g snort -c /etc/snort/nf -i eth0 Now add given below line which will capture the incoming traffic coming on 192.168.1.105(ubuntu IP) network for ICMP protocol.
![zenmap port scan zenmap port scan](https://ibmimedia.com/assets/uploads/media-uploader/nmap-port-scanning-linux-01615522982.jpg)
Therefore be smart and add a rule in snort which will analyst NMAP Ping scan when someone tries to scan your network for identifying a live host of a network.Įxecute given below command in ubuntu’s terminal to open snort local rule file in text editor. Optional: Wireshark (we have added it in our tutorial so that we can clearly confirm all incoming and outgoing packets of a network)Īs we know any attacker will start the attack by identifying host status by sending ICMP packet using ping scan.
![zenmap port scan zenmap port scan](https://www.nesabamedia.com/wp-content/uploads/2019/09/Zenmap-Tampilan.png)
#Zenmap port scan how to#
Today we are going to discuss how to Detect NMAP scan using Snort but before moving ahead kindly read our previous articles related to Snort Installation ( Manually or using apt-respiratory)and its rule configuration to enable it as IDS for your network.īasically, in this article, we are testing Snort against NMAP various scan which will help network security analyst to setup snort rule in such a way so that they become aware of any kind of NMAP scanning.