TP-LINK WR702N Wi-Fi router default password

During the design phase someone had the forethought to make a WiFi AP password that isn’t merely a default. But that’s where this went off the rails. They did the next worst thing, which is to assign a password that gets broadcast publicly: the last eight characters of the MAC address. This will be unique for each device, but it is also promiscuously broadcast to any device that cares to listen.

How are passwords stored in Linux (/etc/shadow)

Let’s take,  from /etc/shadow file:

From the above shown example entry, our topic of interest is the second field(the field with the encoded hash of the password).

$6$lzI56fap$jrSiosb1PF.37iQ2MNKMBBOSkdKyaUpaQlqzbYqZzJ1crEWQArX4keATupJda2S5KvaTGy6sLykD18zaDE50h0

The above shown encoded hash value can be further classified into three different fields as below.

1. The first field is a numerical number that tell’s you the hashing algorithm that’s being used.

  • $1=MD5 hashing Algorithm
  • $2=Blowfish Algorithm
  • $2a=eksblowfish Algorithm
  • $5=SHA-256 Algorithm
  • $6=SHA-512 Algorithm

2. The second field is the salt value

Salt value is nothing but a random data that’s generated to combine with the original password, inorder to increase the strength of the hash..

3.The last field is the hash value of salt+user password.

So in our example entry of root, as shown below:

$6$lzI56fap$jrSiosb1PF.37iQ2MNKMBBOSkdKyaUpaQlqzbYqZzJ1crEWQArX4keATupJda2S5KvaTGy6sLykD18zaDE50h0

The above shown encoded password is using SHA-512 hashing algorithm (because the of $6$)

Salt value is lzI56fap (the content between the second and third $ sign).

Ubuntu Linux lost password, change root password from boot

  1. Reboot your computer
  2. Press SHIFT or ESC at the grub prompt (as earlier)
  3. Select your image, and highlight the line that begins kernel and press ‘e’ to edit
  4. Go to the very end of the line, change the ro to rw and add init=/bin/bash press enter, then press b to boot your system. Your system will boot up to a passwordless root shell
  5. Type in passwd username