The biggest challenge nowadays is to secure the website against  cyber-attacks. Structured Query Language Injection Attack(SQLIA)  is one of the most critical cyber-attack. As a result of SQLIA an  attacker can have the access control on the database of an  application and accordingly can make changes in the critical data  stored on the database server of the website. Authentication plays an  important role in securing critical data. Generally, alphanumeric  passwords are most commonly used for authenticating users in  computer systems but they are highly prone to cyber-attacks.  However, graphical authentication systems have been proposed as a  relevant and possible alternative solution to the traditionally used  text-based (alphanumeric) authentication and the idea is  motivated particularly by the fact that human brain has the ability  to remember images better than text. Graphical passwords are  mainly created by clicking or dragging activities on the pictures or  certain parts of a picture rather than conventional typing of textual  characters. The main objective of the paper is to highlight the  various SQL injection attacks and SQL injection vulnerabilities on  website databases, to study and analyse existing authentication  systems and to propose a secure mechanism of authentication  through color code graphical passwords.