How to identify and crack an NTLM hash

NTLM is an windows credential hash type. It is fast and typically unsalted, which makes weak passwords recoverable quickly on consumer GPU hardware. This page shows how to recognise it and the exact commands to attack it.

All identification runs locally in WebAssembly. The commands below write the hash to a local file on your machine — nothing is sent to this site.

Identifying the hash

The hash identifier on the home page detects NTLM entirely in your browser — your hash is never uploaded. A typical example looks like this:

b4b9b02e6f09a9bd760f388b67351e2b

Cracking NTLM with hashcat

Save the hash to a file and run hashcat in mode -m 1000. Start with a wordlist such as rockyou.txt:

echo 'b4b9b02e6f09a9bd760f388b67351e2b' > hash.txt && hashcat -m 1000 hash.txt /usr/share/wordlists/rockyou.txt

Add a rule set to mutate dictionary words (capitalisation, leetspeak, appended digits) and dramatically widen coverage:

echo 'b4b9b02e6f09a9bd760f388b67351e2b' > hash.txt && hashcat -m 1000 hash.txt /usr/share/wordlists/rockyou.txt -r /usr/share/hashcat/rules/best64.rule

Cracking NTLM with John the Ripper

John the Ripper can attack the same hash with the nt format:

echo 'b4b9b02e6f09a9bd760f388b67351e2b' > hash.txt && john --format=nt --wordlist=/usr/share/wordlists/rockyou.txt hash.txt