John the Ripper

What this covers — Full workflow for John the Ripper (Jumbo): identifying a hash, picking the correct --format= value for every hash type, preparing hashes with the *2john helpers, and every cracking mode flag. For the GPU-heavy equivalents see Hashcat.

Use John the Ripper Jumbo (john-jumbo, the community build shipped on Kali/Parrot). The stock upstream build supports far fewer formats. All commands below assume the Jumbo build.

Table of Contents

1. Quick Workflow
2. Identifying the Hash
3. --format= Flag for Every Hash Type
4. Preparing Hashes — the *2john Helpers
5. Cracking Mode Flags
6. Rules, Masks & Tuning
7. Session, Output & Status Flags
8. Running It — Worked Examples
9. Alternative Approaches & Modern Tooling

1. Quick Workflow

# The canonical three-liner
zip2john secret.zip > hash.txt                 # 1. convert artefact -> john hash
john --format=zip --wordlist=rockyou.txt hash.txt   # 2. crack
john --show --format=zip hash.txt              # 3. reveal cracked passwords

Tip — cracked passwords live in ~/.john/john.pot. John never re-cracks a hash it has already solved. --show reads from the pot file. To force a fresh run, delete or point away from the pot: --pot=/tmp/fresh.pot.

2. Identifying the Hash

# Best-effort identification (installed as `hashid` or `hash-identifier`)
hashid '$6$rounds=5000$abc$...'
hashid -m 'hash'                 # also prints the matching hashcat -m mode

# List every format John supports (grep for what you need)
john --list=formats
john --list=formats | tr ',' '\n' | grep -i ntlm

# Show the subformats/notes for one format
john --list=format-details --format=krb5tgs

Warning — hashid guesses, it does not confirm. Multiple algorithms share a length/shape (e.g. raw MD5 vs NTLM vs raw-MD4 are all 32 hex chars). If the first --format fails, try the siblings in the table below before assuming the hash is wrong.

3. --format= Flag for Every Hash Type

The value passed to --format= is John’s internal format name, not a hashcat mode number. Below are the ones you will actually meet on HTB/CPTS boxes and real engagements. Names are case-insensitive.

Raw / unsalted digests

OS / login hashes

Windows / Active Directory

Databases

Apps, archives & files

Note — formatting upgrade. Store the --format= value in your notes next to the artefact type, not the hash string. On a real box you rarely know the algorithm until you have run the *2john helper — the helper output line usually starts with $name$, which tells you the format immediately (e.g. $krb5tgs$23$... → --format=krb5tgs).

4. Preparing Hashes — the *2john Helpers

Most non-trivial targets are not bare hashes; they are files or captures. The *2john scripts extract a crackable hash string. Run ls /usr/share/john/*2john* and ls /usr/bin/*2john to see what is installed.

ssh2john id_rsa            > ssh.hash
zip2john archive.zip       > zip.hash
rar2john archive.rar       > rar.hash
7z2john archive.7z         > 7z.hash        # may be 7z2john.pl
pdf2john secret.pdf        > pdf.hash
office2john report.docx    > office.hash
keepass2john Database.kdbx > kp.hash
gpg2john secret.gpg        > gpg.hash

# Then crack — format is often auto-detected, but pin it to be safe:
john --wordlist=/usr/share/wordlists/rockyou.txt --format=ssh ssh.hash

5. Cracking Mode Flags

# Classic escalating attack on a shadow file
john --single passwd.hash
john --wordlist=rockyou.txt passwd.hash
john --wordlist=rockyou.txt --rules=Jumbo passwd.hash
john --incremental passwd.hash

Tip — combine --single first, it is free. --single runs in seconds and catches passwords derived from the username (e.g. user admin → admin123, Admin!). Always run it before touching a wordlist.

6. Rules, Masks & Tuning

# Built-in rule sets (defined in /etc/john/john.conf)
john --wordlist=rockyou.txt --rules=Single   hash.txt
john --wordlist=rockyou.txt --rules=Jumbo    hash.txt   # large, thorough
john --wordlist=rockyou.txt --rules=KoreLogic hash.txt

# Mask attack — placeholders:
#   ?l lower  ?u upper  ?d digit  ?s special  ?a all  ?h/?H hex
john --mask='?u?l?l?l?l?d?d' hash.txt
john --mask='Summer?d?d?d?d' hash.txt          # e.g. Summer2024

# Hybrid: wordlist + appended mask
john --wordlist=rockyou.txt --mask='?w?d?d?d' hash.txt   # word + 3 digits

# Fork across CPU cores (Jumbo)
john --fork=4 --wordlist=rockyou.txt hash.txt

# Limit runtime / candidate count
john --wordlist=rockyou.txt --max-run-time=300 hash.txt

7. Session, Output & Status Flags

john --show hash.txt                    # print cracked plaintexts
john --show --format=nt hash.txt        # pin format when showing
john --show=left hash.txt               # show still-uncracked hashes

john --session=engagement hash.txt      # named session (resumable)
john --restore=engagement               # resume it after Ctrl-C / crash
john --status=engagement                # check progress of a running session

# During a live run: press any key for a status line, 'q' to quit gracefully

john --pot=/tmp/custom.pot hash.txt     # use an alternate pot file
john --list=formats                     # all supported formats
john --test --format=sha512crypt        # benchmark one format (speeds)

8. Running It — Worked Examples

Every example is the same two steps: crack with a format + wordlist, then --show the plaintext. Pin --format= so John never guesses wrong on a shared hash length.

NetNTLMv2 (Responder capture)

# Crack — file holds the $NETNTLMv2$ line captured by Responder / ntlmrelayx
john --format=netntlmv2 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt p.agila.ntlmv2

# Show the recovered password
john --show --format=netntlmv2 p.agila.ntlmv2

NTLM / NT hash (dumped from a DC)

john --format=nt --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt ntlm.txt
john --show --format=nt ntlm.txt

Kerberoast — TGS ticket (GetUserSPNs.py)

# Output line begins with $krb5tgs$23$...
john --format=krb5tgs --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt spns.txt
john --show --format=krb5tgs spns.txt

AS-REP roast (GetNPUsers.py)

# Output line begins with $krb5asrep$23$...
john --format=krb5asrep --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt asrep.txt
john --show --format=krb5asrep asrep.txt

Linux /etc/shadow ($6$ = sha512crypt)

# Merge passwd + shadow first so --single can use usernames
unshadow /etc/passwd /etc/shadow > unshadowed.txt
john --format=sha512crypt --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt unshadowed.txt
john --show --format=sha512crypt unshadowed.txt

SSH private key

ssh2john id_rsa > ssh.hash
john --format=ssh --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt ssh.hash
john --show --format=ssh ssh.hash

ZIP archive

zip2john secret.zip > zip.hash
john --format=zip --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt zip.hash
john --show --format=zip zip.hash

KeePass database

keepass2john Database.kdbx > kp.hash
john --format=keepass --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt kp.hash
john --show --format=keepass kp.hash

Office document

office2john report.docx > office.hash
john --format=office --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt office.hash
john --show --format=office office.hash

RAR archive

rar2john archive.rar > rar.hash
# rar2john stamps $rar5$ or $RAR3$ into the line — use rar5 for the former
john --format=rar5 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt rar.hash
john --show --format=rar5 rar.hash

7-Zip archive

7z2john archive.7z > 7z.hash          # may be 7z2john.pl on some builds
john --format=7z --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt 7z.hash
john --show --format=7z 7z.hash

PDF

pdf2john secret.pdf > pdf.hash
john --format=pdf --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt pdf.hash
john --show --format=pdf pdf.hash

GPG / PGP secret key

gpg2john secret.gpg > gpg.hash
john --format=gpg --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt gpg.hash
john --show --format=gpg gpg.hash

NetNTLMv1 (Responder capture)

john --format=netntlm --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt netntlmv1.txt
john --show --format=netntlm netntlmv1.txt

Domain cached creds — MS-Cache v2 (DCC2)

# Format:  username:$DCC2$10240#username#hash
john --format=mscash2 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt dcc2.txt
john --show --format=mscash2 dcc2.txt

bcrypt (htpasswd / app DB, $2a$/$2b$/$2y$)

# Already a hash — no *2john needed. Slow; keep the wordlist tight.
john --format=bcrypt --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt bcrypt.txt
john --show --format=bcrypt bcrypt.txt

Raw MD5 (unsalted digest)

john --format=raw-md5 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt md5.txt
john --show --format=raw-md5 md5.txt

LUKS full-disk encryption

luks2john disk.img > luks.hash        # or point at the LUKS device/partition
john --format=luks --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt luks.hash
john --show --format=luks luks.hash

WPA/WPA2 handshake

# Convert the capture, then crack the PSK
wpapcap2john capture.cap > wpa.hash
john --format=wpapsk --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt wpa.hash
john --show --format=wpapsk wpa.hash

LM hash (legacy Windows)

# LM is uppercase-only and split into two 7-char halves — cracks fast
john --format=lm --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt lm.txt
john --show --format=lm lm.txt

md5crypt ($1$ — Linux/BSD, Cisco IOS type 5)

john --format=md5crypt --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt md5crypt.txt
john --show --format=md5crypt md5crypt.txt

DES crypt (traditional 13-char Unix)

john --format=descrypt --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt descrypt.txt
john --show --format=descrypt descrypt.txt

MySQL 4.1+ / 5+ (leading *)

john --format=mysql-sha1 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt mysql.txt
john --show --format=mysql-sha1 mysql.txt

MSSQL 2012/2014

john --format=mssql12 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt mssql.txt
john --show --format=mssql12 mssql.txt

Oracle 11g

john --format=oracle11 --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt oracle.txt
john --show --format=oracle11 oracle.txt

BitLocker volume

bitlocker2john -i disk.img > bitlocker.hash
john --format=bitlocker --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt bitlocker.hash
john --show --format=bitlocker bitlocker.hash

macOS keychain

keychain2john login.keychain-db > keychain.hash
john --format=keychain --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt keychain.hash
john --show --format=keychain keychain.hash

Bitcoin / crypto wallet

bitcoin2john wallet.dat > wallet.hash
john --format=bitcoin --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt wallet.hash
john --show --format=bitcoin wallet.hash

DPAPI masterkey

# Extract with dpapi.py (impacket) or the DPAPImk2john helper first
john --format=dpapimk --wordlist=/home/daemon-sec/pentest/wordlists/rockyou.txt dpapi.hash
john --show --format=dpapimk dpapi.hash

Tip — benchmark before a slow run. john --test --format=bcrypt prints c/s (candidates per second) so you know whether a wordlist run is minutes or days. Omit --format= to benchmark everything.

9. Alternative Approaches & Modern Tooling

Tip — move salted-but-fast hashes to a GPU. John is CPU-first. For raw MD5/SHA/NTLM and other GPU-friendly algorithms, hashcat on a GPU is often 10–100× faster. Keep John for formats hashcat lacks and for its superb *2john extractors and --single/rules ergonomics.

Note — hashid → mode mapping. hashid -m prints the matching hashcat -m number. There is no clean one-liner mapping to John format names, so keep the table in §3 as your lookup.

Warning — prefer hcxpcapngtool for Wi-Fi. The older wpapcap2john path is fragile with modern captures. Convert with hcxpcapngtool (from hcxtools) to a .hc22000 and crack in hashcat -m 22000, which is the current standard for WPA/WPA2/WPA3-SAE.