Prevent outsiders from using these Google dorks against your web systems

 Modifying the robots.txt file in your server, as follows:

• Prevent indexing from Google by running the following code: 

User-agent: Googlebot

Disallow: /

• Prevent Google from indexing a specific file type by running the following code:

User-agent: Googlebot

Disallow: /*.sql$

• Prevent indexing of a given folder by running the following code:

User-agent: Googlebot

Disallow: /directoryName/

• Prevent indexing from other search engines by running the following code:

User-agent: *

Disallow: /

All these are very basic (but feasible) attacks, but now you have learned how to set up 

the basics of web security, it's time to move on to the next step and learn about the most 

common attacks on web applications.