Nmap - TryHackMe!
Task 2
- What networking constructs are used to direct traffic to the right application on a server?
ports
- How many of these are available on any network-enabled computer?
65535
- [Research] How many of these are considered “well-known”? (These are the “standard” numbers mentioned in the task)?
1024
Task 3
- What is the first switch listed in the help menu for a ‘Syn Scan’ (more on this later!)?
-sS
- Which switch would you use for a “UDP scan”?
-sU
- If you wanted to detect which operating system the target is running on, which switch would you use?
-O
- Nmap provides a switch to detect the version of the services running on the target. What is this switch?
-sV
- The default output provided by nmap often does not provide enough information for a pentester. How would you increase the verbosity?
-v
- Verbosity level one is good, but verbosity level two is better! How would you set the verbosity level to two?
(Note: it’s highly advisable to always use at least this option)
-vv
- What switch would you use to save the nmap results in three major formats?
-oA
- What switch would you use to save the nmap results in a “normal” format?
-oN
- A very useful output format: how would you save results in a “grepable” format?
-oG
- How would you activate this setting?
-A
- How would you set the timing template to level 5?
-T5
- How would you tell nmap to only scan port 80?
-p 80
- How would you tell nmap to scan ports 1000-1500?
-p 1000-1500
- How would you tell nmap to scan all ports?
-p-
- How would you activate a script from the nmap scripting library (lots more on this later!)?
--script
- How would you activate all of the scripts in the “vuln” category?
--script=vuln
Task 5
- Which RFC defines the appropriate behaviour for the TCP protocol?
RFC 793
- If a port is closed, which flag should the server send back to indicate this?
RST
Task 6
- There are two other names for a SYN scan, what are they?
half-open stealth
- Can Nmap use a SYN scan without Sudo permissions (Y/N)?
n
Task 7
- If a UDP port doesn’t respond to an Nmap scan, what will it be marked as?
open|filtered
- When a UDP port is closed, by convention the target should send back a “port unreachable” message. Which protocol would it use to do so?
ICMP
Task 8
- Which of the three shown scan types uses the URG flag?
xmas
- Why are NULL, FIN and Xmas scans generally used?
firewall evasion
- Which common OS may respond to a NULL, FIN or Xmas scan with a RST for every port?
Microsoft windows
Task 9
- How would you perform a ping sweep on the 172.16.x.x network (Netmask: 255.255.0.0) using Nmap? (CIDR notation)
nmap -sn 172.16.0.0/16
Task 10
- What language are NSE scripts written in?
Lua
- Which category of scripts would be a very bad idea to run in a production environment?
intrusive
Task 11
- What optional argument can the ftp-anon.nse script take?
maxlist
Task 12
- What is the filename of the script which determines the underlying OS of the SMB server?
smb-os-discovery.nse
- Read through this script. What does it depend on?
smb-brute
Task 13
- Which simple (and frequently relied upon) protocol is often blocked, requiring the use of the -Pn switch?
ICMP
- [Research] Which Nmap switch allows you to append an arbitrary length of random data to the end of packets?
--data-length
Task 14
This is a practical session, all commands in below youtube video
- Does the target (MACHINE_IP)respond to ICMP (ping) requests (Y/N)?
n
- Perform an Xmas scan on the first 999 ports of the target – how many ports are shown to be open or filtered?
999
- There is a reason given for this – what is it?
no responses
- Perform a TCP SYN scan on the first 5000 ports of the target – how many ports are shown to be open?
5
- Open Wireshark (see Cryillic’s Wireshark Room for instructions) and perform a TCP Connect scan against port 80 on the target, monitoring the results. Make sure you understand what’s going on.
no answer need
- Deploy the ftp-anon script against the box. Can Nmap login successfully to the FTP server on port 21? (Y/N)
y
