PEN Consultants Logo
Don’t Be a Victim: Find your weaknesses before the criminals do. PEN Consultants can help!

This was useful (for an attacker) when password hashing (during authentication) was being performed at the DB level.


Having access to a DB with encrypted (and salted) password hashes can still present a challenge to recovering a significant percentage of the cleartext passwords.  Sure, one will be able to crack some using a decent dictionary/password list, but depending on the cipher used, it can be VERY slow and only recover a small percentage.  If the app sends the cleartext password down to the DB and uses AES_ENCRYPT (for example), then you can easily recover the passwords of active users on the app.

The Attack

From within the MySQL console:

SET global log_output = 'FILE';
SET global general_log_file='/tmp/mysql.log';
SET global general_log = 1;

Now, just monitor for the cleartext passwords being logged in /tmp/mysql.log!

When done, you can turn it off with:

SET global general_log = 0;

Blue Team Solution

First, understand:

  • this example is for MySQL, but can be applied to any DB
  • the type of data present in verbose DB logging. Ex: cleartext passwords

To minimize the chances of this attack:

  1. monitor for “general_log” being set to “1” and generate an alert for it
  2. push password hashing as close to the user as possible.  Example: To the API or app server

If you are looking for a reliable and experienced offensive security service that provides Rock Solid Security, look no further than PEN Consultants for all your information and cybersecurity testing needs. Contact us: