Tuesday, 29 September 2015

How to connect to WiFi using command line Ubuntu, Debian etc.

Tried to upgrade to Ubuntu 15.10 Beta 2, rebooted  and my system was broken. Could not connect to LAN, so my only option was to connect to Wifi via command line to hopefully repair my system.

This is what I did.

First, open a terminal:


If you got WPA like me you need wpa_supplicant to set it up, because iw can only handle WEP.

To bring up your wireless device (most likely wlan0):
sudo -s
ifconfig wlan0 up
#now scan for available wifi networks and note the ssid of your device
iwlist wlan0 scan
In /etc/wpa_supplicant.conf we need to put our ssid and password:
nano /etc/wpa_supplicant.conf
Example config:
                     psk="wifi password"

Ctrl + A to close and save.
To connect:
sudo wpa_supplicant -B -iwlan0 -c/etc/wpa_supplicant.conf -Dwext
Open a second tab/terminal:
sudo dhclient wlan0
Your connection should now work!

Sunday, 6 September 2015

How to crack MD5 hashes with hashcat

OS: Ubuntu 15.04

There is also a GPU version (oclhashcat), but I am on my notebook so I have to use the CPU only version, which - of course - is much slower.

Download the latest hashcat version here: https://hashcat.net/hashcat/

Download a wordlist: https://crackstation.net/buy-crackstation-wordlist-password-cracking-dictionary.htm

Create a MD5 hash: E.g.: 'hello'

echo -n "hello" | md5sum

Next, extract the hashcat archive and create a .txt file with the md5 hash(es) within the folder. Also, save the wordlist in the hashcat folder.

Start hashcat. Dictionary based attack.


./hashcat-cli64.bin -n 2 -m 0 -a 8  test.txt realhuman_phill.txt

-n,   --threads=NUM                 Number of threads
-m,  --hash-type=NUM              Hash-type
-a,  --attack-mode=NUM          Attack-mode

--> use ./hashcat-cli64.bin -h to display all available options.

test.txt is the file with the md5 hash(es) and realhuman_phill.txt is the wordlist.


hashcat will create a filed named hashcat.pot which contains successfully cracked hashes. You can display its contents with cat:

user@user:~/Desktop/hashcat-0.50$ cat '/home/user/Desktop/hashcat-0.50/hashcat.pot'

There you go: hello. 


If you want to read about brute-force (masked) attack have a look here: http://www.unix-ninja.com/p/Exploiting_masks_in_Hashcat_for_fun_and_profit/

Quick example of a brute-force attack for the md5 hash 'cat': 5d41402abc4b2a76b9719d911017c592

./hashcat-cli64.bin -n 2 -m 0 -a 3 test.txt ?a?a?a

?a?a?a specifies to go through all character combinations exactly 3 characters long. ?l?l?l would be lower-case only:
?l = abcdefghijklmnopqrstuvwxyz
?d = 0123456789
?s = !"#$%&'()*+,-./:;<=>?@[]^_`{|}~
?a = ?l?u?d?s

Friday, 28 August 2015

How to install I2P on Ubuntu

Open a terminal and enter:

sudo apt-add-repository ppa:i2p-maintainers/i2p

Update your repositories and install i2p:

sudo apt-get update
sudo apt-get install i2p

Start the I2P router (never as root):

i2prouter start

Configure your browser to connect through I2P. I'd recommend you to use Firefox.

Preferences --> Advanced --> Network tab.

In the Connections section, click on the Settings button. Click the circle next to Manual proxy configuration, enter, port 4444 in the HTTP Proxy field. Enter, port 4445 in the SSL Proxy field. Add localhost and into the "No Proxy for" box.

Saturday, 20 June 2015

How to Register a User Name on IRC/Freenode

I am using pidgin in this guide, but any irc client should be ok.

To install pidgin.
sudo apt-get install pidgin

Add Account
Accounts --> Manage Accounts --> Add

Join a Chat
Buddies - Join a Chat

Register account
/msg NickServ REGISTER password youremail@example.com

Check your email. Follow instructions. Done!

Sunday, 31 May 2015