---
name: "psk-crack"
section: "1"
platform: "linux"
package: "ike-scan"
version: "1.9.5-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/psk-crack"
---

# psk-crack(1)

Crack IKE Aggressive Mode Pre-Shared Keys

## NAME

psk-crack - Crack IKE Aggressive Mode Pre-Shared Keys

## SYNOPSIS

**psk-crack** \[*options*\] \<*psk-parameters-file*\>

**\<psk-parameters-file\>** is a file containing the parameters for the pre-shared key cracking process in the format generated by **ike-scan with the** **--pskcrack (-P)** option.  This file can contain one or more entries.  For multiple entries, each one must be on a separate line.

The program can crack either MD5 or SHA1-based hashes.  The type of hash is automatically determined from the length of the hash (16 bytes for MD5 or 20 bytes for SHA1).  Each entry in the **\<psk-parameters-file\>** is handled separately, so it is possible to crack a mixture of MD5 and SHA1 hashes.

**psk-crack** can also crack the proprietary hash format used by Nortel Contivity / VPN Router systems.  When cracking Nortel format hashes, you need to specify the username of the hash that you are cracking with the **--norteluser (-u)** option.  When cracking Nortel format hashes, you can only crack one hash at a time.

By default, **psk-crack** will perform dictionary cracking using the default dictionary.  The dictionary can be changed with the **--dictionary (-d)** option, or brute-force cracking can be selected with the **--bruteforce (-B)** option.

## DESCRIPTION

**psk-crack** attempts to crack IKE Aggressive Mode pre-shared keys that have previously been gathered using **ike-scan** with the **--pskcrack** option.

**psk-crack** can operate in two different modes:

- 1\)

  Dictionary cracking mode: this is the default mode in which **psk-crack** tries each candidate word from the dictionary file in turn until it finds a match, or all the words in the dictionary have been tried.

- 2\)

  Brute-force cracking mode: in this mode, **psk-crack** tries all possible combinations of a specified character set up to a given length.

## OPTIONS

- **--help or -h**

  Display this usage message and exit.

- **--version or -V**

  Display program version and exit.

- **--verbose or -v**

  Display verbose progress messages.

- **--dictionary=\<f\> or -d \<f\>**

  Set dictionary file to \<f\>.  The default is /usr/local/share/ike-scan/psk-crack-dictionary.

- **--norteluser=\<u\> or -u \<u\>**

  Specify the username for Nortel Contivity cracking. This option is required when cracking pre-shared keys on Nortel Contivity / VPN Router systems.  These systems use a proprietary method to calculate the hash that includes the username. This option is only needed when cracking Nortel format hashes, and should not be used for standard format hashes.

- **--bruteforce=\<n\> or -B \<n\>**

  Select bruteforce cracking up to \<n\> characters.

- **--charset=\<s\> or -c \<s\>**

  Set bruteforce character set to \<s\> Default is "0123456789abcdefghijklmnopqrstuvwxyz"

## AUTHOR

Roy Hills \<Roy.Hills@nta-monitor.com\>