Ncrack

High-speed network authentication cracker (Nmap project).

KaliParrotLinuxhigh

pkg: ncrack

Ncrack brute-forces network logins (RDP, SSH, FTP, etc.) with Nmap-style targeting and timing controls.

Syntax

ncrack [-p service] {host}

Example

ncrack -p 3389 10.0.0.5

Brute-forces RDP (3389) on the host using built-in defaults.

Options & flags

What each switch does. Toggle them in the builder below to assemble a command.

-p <3389>Service/port to attack.
--user <admin>Username(s).
-U <users.txt>Username file.
-P <rockyou.txt>Password file.
-T <4>Timing template 0-5.

Command builder

Tick options (and fill any values) to build a ready-to-copy command.

ncrack

Usage examples

ncrack -p 3389 10.0.0.5

Brute-force RDP.

ncrack -p 22 --user root -P rockyou.txt 10.0.0.5

Brute-force SSH for root.

Advantages
  • Nmap-style targeting/timing
  • Good for RDP/SSH at scale
  • Adaptive engine
Disadvantages
  • Loud; causes lockouts
  • Fewer modules than Hydra
  • Needs careful timing
Tags
#brute-force#rdp

Official docs: Ncrack

Related commands

Frequently asked questions

What is Ncrack used for?
Ncrack brute-forces network logins (RDP, SSH, FTP, etc.) with Nmap-style targeting and timing controls.
What is an example Ncrack command?
A common example is: ncrack -p 3389 10.0.0.5 — Brute-forces RDP (3389) on the host using built-in defaults.
Is Ncrack part of Kali Linux?
Yes. Ncrack ships with Kali Linux (and Parrot OS). If missing, install it with: sudo apt install ncrack.
What category of security tool is Ncrack?
Ncrack is a Password Attacks tool with a high-risk profile when run against a live target.

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