1 00:00:00,630 --> 00:00:01,770 Hello, my name is Stephan. 2 00:00:01,770 --> 00:00:03,570 Welcome to our Nmap lecture. 3 00:00:03,570 --> 00:00:08,400 In this lecture, we will dive into the exciting world of network reconnaissance. 4 00:00:08,400 --> 00:00:16,470 So today we will explore a crucial task for penetration testers and system administrators, like finding 5 00:00:16,470 --> 00:00:18,120 online hosts. 6 00:00:18,120 --> 00:00:25,980 So we will discover how Nmap, the go to tool for network scanning, offers enhanced host detection 7 00:00:25,980 --> 00:00:31,350 capabilities and provides valuable insights beyond the traditional ping utilities. 8 00:00:32,000 --> 00:00:36,710 Segment one The Importance of Host Discovery. 9 00:00:37,010 --> 00:00:44,330 Before we begin our exploration of Nmp's capabilities, let's understand why finding online hosts is 10 00:00:44,330 --> 00:00:51,920 such a fundamental task in today's interconnected world where networks span vast geographic areas on 11 00:00:51,920 --> 00:00:53,840 the Internet links countless devices. 12 00:00:53,870 --> 00:01:00,360 Being able to identify active machines within a network or on the Internet is crucial. 13 00:01:00,380 --> 00:01:08,120 Penetration testers rely on host discovery to identify potential entry points and vulnerabilities, 14 00:01:08,120 --> 00:01:14,900 while system administrators use it to monitor network health and ensure the smooth operation of their 15 00:01:14,900 --> 00:01:15,680 systems. 16 00:01:16,600 --> 00:01:20,110 Segment two of the Nmap pink scan. 17 00:01:20,110 --> 00:01:28,120 So Nmap pink scan feature takes host detection to the next level by sending a series of probes so the 18 00:01:28,120 --> 00:01:37,450 Nmap goes beyond the icnp echo request commonly used by traditional ping utilities like ping here for 19 00:01:37,450 --> 00:01:42,760 example, pink less pink to ourselves here on our machine. 20 00:01:44,690 --> 00:01:46,850 And as you can see, this is just a pink, right? 21 00:01:46,850 --> 00:01:52,430 So Nmap goes beyond this echo request commonly used like this. 22 00:01:52,700 --> 00:02:00,200 So this comprehensive approach increases the accuracy and reliability of host detection, allowing us 23 00:02:00,200 --> 00:02:05,150 to gather valuable information about the online entities within a target network. 24 00:02:05,150 --> 00:02:07,730 So segment three. 25 00:02:08,420 --> 00:02:12,710 We can execute a ping scan to launch a ping scan with an Nmap. 26 00:02:12,710 --> 00:02:15,200 So we we will utilize this command here. 27 00:02:15,200 --> 00:02:20,660 So this code here, so Nmap scan and here we will enter our target. 28 00:02:20,660 --> 00:02:21,200 Right? 29 00:02:21,200 --> 00:02:23,840 So the SDN here. 30 00:02:25,460 --> 00:02:33,440 Option interacts Nmap to disable port scanning and focus solely on the host discovery phase. 31 00:02:33,470 --> 00:02:41,810 It's worth noting that the Nmap supports a wide range of target specifications, including IP version 32 00:02:41,810 --> 00:02:50,690 four, IP version six addresses, host names and network ranges defined using the wildcards and cedar 33 00:02:50,720 --> 00:02:51,680 notations. 34 00:02:51,680 --> 00:02:57,800 So, for example, to scan the local network, we will first need to understand learn what is the local 35 00:02:57,800 --> 00:03:00,290 network IP starts with here and now. 36 00:03:00,290 --> 00:03:03,590 We will use this Nmap as n here. 37 00:03:03,590 --> 00:03:07,370 192.168.0. 38 00:03:07,700 --> 00:03:11,390 13.1 and 24 here. 39 00:03:12,220 --> 00:03:20,980 So and as you can see now, we are scanning the our Host So segment for analyzing the results. 40 00:03:20,980 --> 00:03:28,690 So once the pink scan is complete, a Nmap provides us with a comprehensive list of hosts that responded 41 00:03:28,690 --> 00:03:30,550 to its probing packets. 42 00:03:30,550 --> 00:03:38,110 So these active machines represent the online entities within the target network segment or the Internet. 43 00:03:38,110 --> 00:03:44,530 So by examining the results, we can gain insights into the network composition, identifying potential 44 00:03:44,560 --> 00:03:51,280 bottlenecks or misconfigurations and further refine our understanding of the target environment. 45 00:03:53,200 --> 00:03:58,640 Segment five uncovering additional details and maps. 46 00:03:58,660 --> 00:04:01,810 Pink scans over more than just the host discovery. 47 00:04:01,810 --> 00:04:09,490 So when executed with sufficient privileges on local Ethernet networks, Nmap can also identify Mac 48 00:04:09,490 --> 00:04:13,640 addresses and associated vendors based on Mac address identifiers. 49 00:04:13,660 --> 00:04:19,360 This additional information allows us to gain insight into the devices present on the network, aiding 50 00:04:19,360 --> 00:04:22,120 in network inventory management and security assessments. 51 00:04:22,120 --> 00:04:27,790 So in order to do that we will just add pseudo before Nmap to run it with pseudo privileges. 52 00:04:27,790 --> 00:04:29,980 And here you will see. 53 00:04:31,040 --> 00:04:33,410 Also the Mac addresses right here. 54 00:04:34,190 --> 00:04:42,140 Segment six Under the Hood How Nmap works to understand the mechanics behind the Nmap pink. 55 00:04:42,500 --> 00:04:45,080 So this pink scans here. 56 00:04:45,080 --> 00:04:48,650 So let's delve into the inner workings of this powerful tool. 57 00:04:48,680 --> 00:04:58,020 This is an option, as mentioned earlier, disables port scanning and focuses solely on the host discovery 58 00:04:58,070 --> 00:05:04,820 interface depending on the user's privileges and Map utilizes various techniques to determine the online 59 00:05:04,820 --> 00:05:05,990 status of a host. 60 00:05:05,990 --> 00:05:09,290 So when executed as privileged users here. 61 00:05:09,860 --> 00:05:19,010 So Nmap employs a combination of techniques, so it sends TCP sync a packet to the port 443 and TCP 62 00:05:19,010 --> 00:05:19,550 acknowledge. 63 00:05:19,550 --> 00:05:28,790 So TCP, TCP, TCP packet to the port 80 and ICMP echo and timestamp requests. 64 00:05:28,790 --> 00:05:37,620 So these the probe helps to ensure that even hosts with restrictive firewall rules can be detected. 65 00:05:37,620 --> 00:05:44,580 So if the user running Nmap doesn't have the capability to send raw packets, it employs the connect 66 00:05:44,580 --> 00:05:53,130 system call to the to send the syn packets on port 80 and port 443. 67 00:05:55,250 --> 00:05:59,910 Segment seven exploring local Ethernet networks. 68 00:05:59,930 --> 00:06:08,720 When scanning local Ethernet networks as privileged users, Nmap activates ARP Neighbor Discovery so 69 00:06:08,720 --> 00:06:11,840 further enhancing host detection capabilities. 70 00:06:11,840 --> 00:06:19,670 So by leveraging ARP request, Nmap can identify Mac addresses and associated vendors. 71 00:06:19,670 --> 00:06:28,010 And this information becomes invaluable in understanding the composition of the network and identifying 72 00:06:28,010 --> 00:06:31,010 the types of devices connected. 73 00:06:32,040 --> 00:06:41,160 So in conclusion, Nmap revolutionizes the way we discover online hosts with its robust pink scan capabilities 74 00:06:41,160 --> 00:06:47,760 and by leveraging Nmap, extensive probing techniques and privileged user functionalities, penetration 75 00:06:47,760 --> 00:06:53,550 testers and system administrators can gain a comprehensive understanding of their networks. 76 00:06:53,550 --> 00:06:59,190 Remember, host Discovery is the first step towards a secure and efficient system. 77 00:06:59,190 --> 00:07:05,610 So go ahead, unleash the power of Nmap and embark your network reconnaissance journey.