CySA+ Tools and commands
nmap - ANS-A network-vulnerability scanner.
nmap -O - ANS-Performs OS fingerprinting
nmap -sV - ANS-Service version identification.
Determines what version services are running and on what ports
nmap -sT - ANS-TcpConnect scan. Scans by attempting the TCP three way handshake
connection (easiest to detect, but most reliable). This is the default scan that will be performed if
no flags are added (so just "nmap hostname")
nmap -sX - ANS-Xmas scan. Scans by setting all flags on TCP packet (FIN, URG, PUSH). If the
target doesn't respond, the port is open. If the connection resets (RST), the port is closed. Does
not work on Windows machines.
nmap -sU - ANS-UDP scan.
nmap -sS - ANS-Performs a stealth scan which limits the visibility of the scan on the network.
SYN scan. Just send SYN packet. Requires raw socket access (root user access).
netstat - ANS-A universal command-line utility used to examine the TCP/IP connections open
on a given host.
netstat -a - ANS-Displays active tcp and udp connections.
netstat -0 - ANS-Identify a process using a connection.
Once you know the process, you can terminate it.
netstat -e - ANS-Displays ethernet statistics on sent/received data.
Useful in a similar way to netflow; you can see if there is a suspicious amount of data usage,
possibly that you did not do, alerting you that there could be someone stealing your data.
netstat -r - ANS-Displays the routing table.
Useful because you can see if you have unwanted/backdoor routes.
-ps - ANS-Linux command used to list the currently running processes and their PIDs
-top - ANS-Linux command like -ps, but also provides sorting processes by top usage
-df - ANS-Linux command that reports file system disk space usage
, -w - ANS-Linux command that shows who is logged on and what they are doing
service --status-all - ANS-Linux command that lists the state of services controlled by System
-dd - ANS-A Linux command that clones drives using bit-by-bit copy.
use with the command bs to set the block size
-dd bs=64k if=/etc of=/etc
if is the input file, of is the output file
use conv=noerror to continue to copy if there are read errors.
md5sum - ANS-Linux command that will compute and check MD5 message digest
md5sum <filename>
nslookup/dig - ANS-a tool used to query the DNS server for information such as IP addresses,
canonical names, cache timers, ect. Good for troubleshooting DNS servers. dig is more
detailed.
host - ANS-Unix command. DNS lookup utility, finding the IP address of a domain name. It also
performs reverse lookups, finding the domain name associated with an IP address.
whois - ANS-query and response protocol that is widely used for querying databases that store
the registered users of an Internet resource, such as a domain name or an IP address block.
Will provide details such as company, names, addresses, phone numbers, emails, and more for
a given domain.
tcpdump - ANS-A Unix command-line protocol analyzer. It allows the user to display TCP/IP and
other packets being transmitted or received over a network to which the computer is attached.
Qualys - ANS-Vulnerability scanner that is good, popular, allows for asset grouping and
inventorying, scan comparisons, set groups, schedule scans
Nessus - ANS-Vulnerability scanner comparable to Qualys
Nexpose - ANS-Vulnerability scanner comparable to Qualys and Nessus
OpenVAS - ANS-Open source vulnerability scanner. low cost (free). OpenVAS is a fork of the
original Nessus.
Nikto - ANS-Web application vulnerability scanner (other tools scan databases, but Nikto scans
the coding of the web server. Nikto is a great supplemental scanner to use with other
vulnerability scanners to gain a different perspective.)
nmap - ANS-A network-vulnerability scanner.
nmap -O - ANS-Performs OS fingerprinting
nmap -sV - ANS-Service version identification.
Determines what version services are running and on what ports
nmap -sT - ANS-TcpConnect scan. Scans by attempting the TCP three way handshake
connection (easiest to detect, but most reliable). This is the default scan that will be performed if
no flags are added (so just "nmap hostname")
nmap -sX - ANS-Xmas scan. Scans by setting all flags on TCP packet (FIN, URG, PUSH). If the
target doesn't respond, the port is open. If the connection resets (RST), the port is closed. Does
not work on Windows machines.
nmap -sU - ANS-UDP scan.
nmap -sS - ANS-Performs a stealth scan which limits the visibility of the scan on the network.
SYN scan. Just send SYN packet. Requires raw socket access (root user access).
netstat - ANS-A universal command-line utility used to examine the TCP/IP connections open
on a given host.
netstat -a - ANS-Displays active tcp and udp connections.
netstat -0 - ANS-Identify a process using a connection.
Once you know the process, you can terminate it.
netstat -e - ANS-Displays ethernet statistics on sent/received data.
Useful in a similar way to netflow; you can see if there is a suspicious amount of data usage,
possibly that you did not do, alerting you that there could be someone stealing your data.
netstat -r - ANS-Displays the routing table.
Useful because you can see if you have unwanted/backdoor routes.
-ps - ANS-Linux command used to list the currently running processes and their PIDs
-top - ANS-Linux command like -ps, but also provides sorting processes by top usage
-df - ANS-Linux command that reports file system disk space usage
, -w - ANS-Linux command that shows who is logged on and what they are doing
service --status-all - ANS-Linux command that lists the state of services controlled by System
-dd - ANS-A Linux command that clones drives using bit-by-bit copy.
use with the command bs to set the block size
-dd bs=64k if=/etc of=/etc
if is the input file, of is the output file
use conv=noerror to continue to copy if there are read errors.
md5sum - ANS-Linux command that will compute and check MD5 message digest
md5sum <filename>
nslookup/dig - ANS-a tool used to query the DNS server for information such as IP addresses,
canonical names, cache timers, ect. Good for troubleshooting DNS servers. dig is more
detailed.
host - ANS-Unix command. DNS lookup utility, finding the IP address of a domain name. It also
performs reverse lookups, finding the domain name associated with an IP address.
whois - ANS-query and response protocol that is widely used for querying databases that store
the registered users of an Internet resource, such as a domain name or an IP address block.
Will provide details such as company, names, addresses, phone numbers, emails, and more for
a given domain.
tcpdump - ANS-A Unix command-line protocol analyzer. It allows the user to display TCP/IP and
other packets being transmitted or received over a network to which the computer is attached.
Qualys - ANS-Vulnerability scanner that is good, popular, allows for asset grouping and
inventorying, scan comparisons, set groups, schedule scans
Nessus - ANS-Vulnerability scanner comparable to Qualys
Nexpose - ANS-Vulnerability scanner comparable to Qualys and Nessus
OpenVAS - ANS-Open source vulnerability scanner. low cost (free). OpenVAS is a fork of the
original Nessus.
Nikto - ANS-Web application vulnerability scanner (other tools scan databases, but Nikto scans
the coding of the web server. Nikto is a great supplemental scanner to use with other
vulnerability scanners to gain a different perspective.)
