NMAP

Cheat Sheet

1. Target Specification

SWITCH
EXAMPLE
DESCRIPTION

nmap 192.168.1.1

Scan a single IP

nmap 192.168.1.1 192.168.2.1

Scan specific IPs

nmap 192.168.1.1-254

Scan a range

nmap scanme.nmap.org

Scan a domain

nmap 192.168.1.0/24

Scan using CIDR notation

-iL

nmap -iL targets.txt

Scan targets from a file

-iR

nmap -iR 100

Scan 100 random hosts

--exclude

nmap --exclude 192.168.1.1

Exclude listed hosts

2. Nmap Scan Techniques

SWITCH
EXAMPLE
DESCRIPTION

-sS

nmap 192.168.1.1 -sS

TCP SYN port scan (Default)

-sT

nmap 192.168.1.1 -sT

TCP connect port scan (Default without root privilege)

-sU

nmap 192.168.1.1 -sU

UDP port scan

-sA

nmap 192.168.1.1 -sA

TCP ACK port scan

-sW

nmap 192.168.1.1 -sW

TCP Window port scan

-sM

nmap 192.168.1.1 -sM

TCP Maimon port scan

3. Host Discovery

SWITCH
EXAMPLE
DESCRIPTION

-sL

nmap 192.168.1.1-3 -sL

No Scan. List targets only

-sn

nmap 192.168.1.1/24 -sn

Disable port scanning. Host discovery only.

-Pn

nmap 192.168.1.1-5 -Pn

Disable host discovery. Port scan only.

-PS

nmap 192.168.1.1-5 -PS22-25,80

TCP SYN discovery on port x. Port 80 by default

-PA

nmap 192.168.1.1-5 -PA22-25,80

TCP ACK discovery on port x. Port 80 by default

-PU

nmap 192.168.1.1-5 -PU53

UDP discovery on port x. Port 40125 by default

-PR

nmap 192.168.1.1-1/24 -PR

ARP discovery on local network

-n

nmap 192.168.1.1 -n

Never do DNS resolution

4. Port Specification

SWITCH
EXAMPLE
DESCRIPTION

-p

nmap 192.168.1.1 -p 21

Port scan for port x

-p

nmap 192.168.1.1 -p 21-100

Port range

-p

nmap 192.168.1.1 -p U:53,T:21-25,80

Port scan multiple TCP and UDP ports

-p

nmap 192.168.1.1 -p-

Port scan all ports

-p

nmap 192.168.1.1 -p http,https

Port scan from service name

-F

nmap 192.168.1.1 -F

Fast port scan (100 ports)

--top-ports

nmap 192.168.1.1 --top-ports 2000

Port scan the top x ports

-p-65535

nmap 192.168.1.1 -p-65535

Leaving off initial port in range makes the scan start at port 1

-p0-

nmap 192.168.1.1 -p0-

Leaving off end port in range makes the scan go through to port 65535

5. Service and Version Detection

SWITCH
EXAMPLE
DESCRIPTION

-sV

nmap 192.168.1.1 -sV

Attempts to determine the version of the service running on port

-sV --version-intensity

nmap 192.168.1.1 -sV --version-intensity 8

Intensity level 0 to 9. Higher number increases possibility of correctness

-sV --version-light

nmap 192.168.1.1 -sV --version-light

Enable light mode. Lower possibility of correctness. Faster

-sV --version-all

nmap 192.168.1.1 -sV --version-all

Enable intensity level 9. Higher possibility of correctness. Slower

-A

nmap 192.168.1.1 -A

Enables OS detection, version detection, script scanning, and traceroute

6. OS Detection

SWITCH
EXAMPLE
DESCRIPTION

-O

nmap 192.168.1.1 -O

Remote OS detection using TCP/IP stack fingerprinting

-O --osscan-limit

nmap 192.168.1.1 -O --osscan-limit

If at least one open and one closed TCP port are not found it will not try OS detection against host

-O --osscan-guess

nmap 192.168.1.1 -O --osscan-guess

Makes Nmap guess more aggressively

-O --max-os-tries

nmap 192.168.1.1 -O --max-os-tries 1

Set the maximum number x of OS detection tries against a target

-A

nmap 192.168.1.1 -A

Enables OS detection, version detection, script scanning, and traceroute

7. Timing and Performance

SWITCH
EXAMPLE
DESCRIPTION

-T0

nmap 192.168.1.1 -T0

Paranoid (0) Intrusion Detection System evasion

-T1

nmap 192.168.1.1 -T1

Sneaky (1) Intrusion Detection System evasion

-T2

nmap 192.168.1.1 -T2

Polite (2) slows down the scan to use less bandwidth and use less target machine resources

-T3

nmap 192.168.1.1 -T3

Normal (3) which is default speed

-T4

nmap 192.168.1.1 -T4

Aggressive (4) speeds scans; assumes you are on a reasonably fast and reliable network

-T5

nmap 192.168.1.1 -T5

Insane (5) speeds scan; assumes you are on an extraordinarily fast network

8. Timing and Performance Switches

SWITCH
EXAMPLE INPUT
DESCRIPTION

--host-timeout <time>

1s; 4m; 2h

Give up on target after this long

--min-rtt-timeout/max-rtt-timeout/initial-rtt-timeout <time>

1s; 4m; 2h

Specifies probe round trip time

--min-hostgroup/max-hostgroup <size<size>>

50; 1024

Parallel host scan group sizes

--min-parallelism/max-parallelism <numprobes>

10; 1

Probe parallelization

--max-retries <tries>

3

Specify the maximum number of port scan probe retransmissions

--min-rate <number>

100

Send packets no slower than <number> per second

--max-rate <number>

100

Send packets no faster than <number> per second

9. NSE Scripts

SWITCH
EXAMPLE
DESCRIPTION

-sC

nmap 192.168.1.1 -sC

Scan with default NSE scripts. Considered useful for discovery and safe

--script default

nmap 192.168.1.1 --script default

Scan with default NSE scripts. Considered useful for discovery and safe

--script

nmap 192.168.1.1 --script=banner

Scan with a single script. Example banner

--script

nmap 192.168.1.1 --script=http*

Scan with a wildcard. Example http

--script

nmap 192.168.1.1 --script=http,banner

Scan with two scripts. Example http and banner

--script

nmap 192.168.1.1 --script "not intrusive"

Scan default, but remove intrusive scripts

--script-args

nmap --script snmp-sysdescr --script-args snmpcommunity=admin 192.168.1.1

NSE script with arguments

10. Useful NSE Script Examples

COMMAND
DESCRIPTION

nmap -Pn --script=http-sitemap-generator scanme.nmap.org

http site map generator

nmap -n -Pn -p 80 --open -sV -vvv --script banner,http-title -iR 1000

Fast search for random web servers

nmap -Pn --script=dns-brute domain.com

Brute forces DNS hostnames guessing subdomains

nmap -n -Pn -vv -O -sV --script smb-enum*,smb-ls,smb-mbenum,smb-os-discovery,smb-s*,smb-vuln*,smbv2* -vv 192.168.1.1

Safe SMB scripts to run

nmap --script whois* domain.com

Whois query

nmap -p80 --script http-unsafe-output-escaping scanme.nmap.org

Detect cross site scripting vulnerabilities

nmap -p80 --script http-sql-injection scanme.nmap.org

Check for SQL injections

11. Firewall / IDS Evasion and Spoofing

SWITCH
EXAMPLE
DESCRIPTION

-f

nmap 192.168.1.1 -f

Requested scan (including ping scans) use tiny fragmented IP packets. Harder for packet filters

--mtu

nmap 192.168.1.1 --mtu 32

Set your own offset size

-D

nmap -D 192.168.1.101,192.168.1.102,192.168.1.103,192.168.1.23 192.168.1.1

Send scans from spoofed IPs

-D

nmap -D decoy-ip1,decoy-ip2,your-own-ip,decoy-ip3,decoy-ip4 remote-host-ip

Above example explained

-S

nmap -S www.microsoft.com www.facebook.com

Scan Facebook from Microsoft (-e eth0 -Pn may be required)

-g

nmap -g 53 192.168.1.1

Use given source port number

--proxies

nmap --proxies http://192.168.1.1:8080, http://192.168.1.2:8080 192.168.1.1

Relay connections through HTTP/SOCKS4 proxies

--data-length

nmap --data-length 200 192.168.1.1

Appends random data to sent packets

Example IDS Evasion command

12. Ouput

SWITCH
EXAMPLE
DESCRIPTION

-oN

nmap 192.168.1.1 -oN normal.file

Normal output to the file normal.file

-oX

nmap 192.168.1.1 -oX xml.file

XML output to the file xml.file

-oG

nmap 192.168.1.1 -oG grep.file

Grepable output to the file grep.file

-oA

nmap 192.168.1.1 -oA results

Output in the three major formats at once

-oG --

nmap 192.168.1.1 -oG --

Grepable output to screen. -oN -, -oX – also usable

--append-output

nmap 192.168.1.1 -oN file.file --append-output

Append a scan to a previous scan file

-v

nmap 192.168.1.1 -v

Increase the verbosity level (use -vv or more for greater effect)

-d

nmap 192.168.1.1 -d

Increase debugging level (use -dd or more for greater effect)

--reason

nmap 192.168.1.1 --reason

Display the reason a port is in a particular state, same output as -vv

--open

nmap 192.168.1.1 --open

Only show open (or possibly open) ports

--packet-trace

nmap 192.168.1.1 -T4 --packet-trace

Show all packets sent and received

13. Helpful Nmap Output examples

Commands
Description

nmap -p80 -sV -oG – –open 192.168.1.1/24 | grep open

Scan des serveurs Web et filtrage pour afficher les adresses IP qui les exécutent

nmap -iR 10 -n -oX out.xml | grep Nmap | cut -d " " -f5 > live-hosts.txt

Génération d'une liste des adresses IP des hôtes actifs

nmap -iR 10 -n -oX out2.xml | grep Nmap | cut -d " " -f5 >> live-hosts.txt

Ajout d'une adresse IP à la liste des hôtes actifs

ndiff scanl.xml scan2.xml

Comparaison des résultats de la commande nmap à l'aide de l'outil ndif

xsltproc nmap.xml -o nmap.html

Conversion des fichiers XML nmap en fichiers HTML

grep open results.nmap | sed -r 's/ +/ /g' | sort | uniq -c | sort -rn | less

Liste triée par ordre décroissant de la fréquence à laquelle les ports sont ouverts

14. Miscellaneous Nmap Flags

Drapeau
Exemple
Description

-6

nmap -6 2607:f0d0:1002:51::4

Activation de l'analyse IPv6

-h

nmap -h

Affichage de l'aide de la commande nmap

Troubleshooting

If error “dnet: Failed to open device eth2

Add following parameter

--unprivileged

Credits : Nmap Cheat Sheet 2023: All the Commands, Flags & Switches