1 00:00:00,700 --> 00:00:06,370 Hello, my name is Stephanie, and in this lecture you will learn how to discover open ports with Nmap. 2 00:00:06,400 --> 00:00:13,000 In the realm of network reconnaissance, one of the most valuable tasks is to determine the port states 3 00:00:13,000 --> 00:00:14,200 of a target. 4 00:00:14,230 --> 00:00:22,330 This process is commonly known as port scanning, so Nmap, the versatile network scanning tool, excels 5 00:00:22,360 --> 00:00:27,670 at this task, so providing a valuable insights into the running services on a target. 6 00:00:27,670 --> 00:00:34,450 So in this segment we will explore essential Nmap options related to port scanning and learn how to 7 00:00:34,450 --> 00:00:38,500 effectively list open ports on a target segment. 8 00:00:38,530 --> 00:00:39,340 One. 9 00:00:40,070 --> 00:00:44,230 Launching the default scan to initiate a default scan with Nmap. 10 00:00:44,240 --> 00:00:52,340 All you need to is the target information, which can be an IP address hostname or even a network range. 11 00:00:52,340 --> 00:00:54,290 So let's take a look at this example here. 12 00:00:54,290 --> 00:00:56,270 So Nmap could easily. 13 00:00:57,800 --> 00:00:58,640 Dot com. 14 00:00:59,090 --> 00:01:07,100 So here this command will initiate a scan on the target host Qatar Telecom and provide detailed information 15 00:01:07,100 --> 00:01:11,210 about the open ports and their corresponding services. 16 00:01:11,240 --> 00:01:13,490 And here it is, the output here. 17 00:01:13,490 --> 00:01:19,100 And as you can see, Tron 988 filtered TCP ports and so on. 18 00:01:19,100 --> 00:01:21,020 So you will also learn what is here. 19 00:01:21,020 --> 00:01:23,150 So in segment two, which is. 20 00:01:24,240 --> 00:01:28,530 Segment two, so you will understand the scan results here. 21 00:01:28,530 --> 00:01:35,640 So the scan result generated by Nmap offer a crucial information about a target host. 22 00:01:35,670 --> 00:01:44,000 Let me actually open the grommet here and I will draw things on the screen to explain this better. 23 00:01:44,010 --> 00:01:45,570 So here. 24 00:01:46,940 --> 00:01:55,700 Here we have alongside with the IPv4 and IPv6 addresses, reverse DNS names and latency details. 25 00:01:55,730 --> 00:02:04,010 The results highlight the ports and their respective states, and the port states are categorized like 26 00:02:04,010 --> 00:02:04,580 this here. 27 00:02:04,580 --> 00:02:07,640 So in first year we have open. 28 00:02:08,950 --> 00:02:09,850 Open ports. 29 00:02:09,880 --> 00:02:12,370 This this here in open here. 30 00:02:12,370 --> 00:02:15,190 As you can see, all of these ports are open here. 31 00:02:15,280 --> 00:02:25,270 So with this we are indicating so Nmap is indicates that a service is actively listening for connections 32 00:02:25,270 --> 00:02:27,730 on the port open here. 33 00:02:27,730 --> 00:02:30,400 And also we have the closed. 34 00:02:32,500 --> 00:02:33,550 With this here. 35 00:02:34,240 --> 00:02:42,760 Nmap indicates to us that the probes were received, but no service was detected on the port. 36 00:02:42,760 --> 00:02:45,370 And we also have the filtered. 37 00:02:49,400 --> 00:02:50,000 Filter it. 38 00:02:50,300 --> 00:02:56,870 So this indicates that the probe's reception could not be determined possibly due to the filtering mechanisms. 39 00:02:56,870 --> 00:02:59,870 And we also have on filtered. 40 00:03:06,850 --> 00:03:13,840 So with this here, iMap indicates us that the probes were received, but the state couldn't be established 41 00:03:13,840 --> 00:03:17,350 and we also have open filter it here. 42 00:03:18,010 --> 00:03:24,310 This means that indicates that the port appears to be either open or filtered, but the state couldn't 43 00:03:24,310 --> 00:03:25,000 be determined. 44 00:03:25,000 --> 00:03:27,850 And we also have the. 45 00:03:29,410 --> 00:03:35,800 Klaus filtered here, which indicates that the port appears to be either closed or filtered, but the 46 00:03:35,800 --> 00:03:37,450 state couldn't be determined. 47 00:03:39,060 --> 00:03:41,430 And here we will also learn the. 48 00:03:45,310 --> 00:03:47,500 How to customize Nmap scans. 49 00:03:47,500 --> 00:03:55,660 So while the default scan provides a valuable information, Nmap offers a plethora of customization 50 00:03:55,660 --> 00:03:56,230 options. 51 00:03:56,230 --> 00:04:05,020 So for instance, for instance, you can specify alternative DNS server using the DNS servers option 52 00:04:05,020 --> 00:04:09,670 like this DNS servers option to control DNS resolution during the scan. 53 00:04:09,760 --> 00:04:16,630 For example, this Nmap DNS server here and we will enter the Google DNS here one eight, eight eight 54 00:04:16,630 --> 00:04:16,990 here. 55 00:04:16,990 --> 00:04:26,890 And after that comma we will type and 8.8.94.4 here and now we will do console.com. 56 00:04:26,890 --> 00:04:36,390 So by providing this DNS server, Nmap will utilize this servers for hostname resolution and here further. 57 00:04:36,620 --> 00:04:43,720 Furthermore, Nmap performs host discovery to determine if the target is online before conducting port 58 00:04:43,720 --> 00:04:50,870 scanning and you can skip the host discovery step using the pen option here. 59 00:04:53,350 --> 00:04:59,470 After Nmap p an uppercase and lowercase n here. 60 00:05:00,220 --> 00:05:04,480 And here you will see another result. 61 00:05:04,480 --> 00:05:04,990 It might. 62 00:05:05,020 --> 00:05:05,860 It might take here. 63 00:05:05,860 --> 00:05:08,860 Actually, let me use the sudo here. 64 00:05:09,010 --> 00:05:10,990 Sudo enter password. 65 00:05:10,990 --> 00:05:11,710 That's it. 66 00:05:12,100 --> 00:05:20,620 And here this command will directly indicate initiate port scanning without prior post discovery with 67 00:05:20,650 --> 00:05:24,850 uppercase and lowercase n options here. 68 00:05:39,500 --> 00:05:46,370 And here Nmap employs various tick scan techniques depending on the user's privileges, and the default 69 00:05:46,370 --> 00:05:55,550 scan can utilize a synchronized scan, stealth scan or TCP connect scan here so these techniques ensure 70 00:05:55,550 --> 00:06:00,670 comprehensive port scanning while considering the user's pillages and network environment. 71 00:06:00,680 --> 00:06:08,540 So port scanning with Nmap unravels the network services running on a target, enabling us to gain insights 72 00:06:08,540 --> 00:06:15,680 into potential vulnerabilities and secure our networks by understanding the scan results here, customizing 73 00:06:15,680 --> 00:06:22,730 the Nmap scans and being aware of the underlying scan techniques so we can effectively explore open 74 00:06:22,730 --> 00:06:26,100 ports and their associated services here. 75 00:06:26,120 --> 00:06:34,460 Now, as you can see, we are seeing services FTP, Smtp, FTP domain, Http, Pop3, iMap and so on. 76 00:06:34,460 --> 00:06:42,390 So equip yourself with Nmap port scanning progress and unlock the secrets hidden within your network.