Although there are lots of method and devices available for authentication, each of the authentication that we use has their own limitations. Below are the authentication systems that we are using and their limitations:
ID and password are the most common and widely used authentication method. Although it is one of the widely used methods it carries huge security risk. One of the biggest problems with this system is that anyone can guess the password and can be shared knowingly or unknowingly. Also, the no. of the password will increase with the no. of service that user uses. It is insecure to use a single password for all the websites, so it is recommended to create a unique password for each website.
Users cannot remember all the passwords that they have, and they might write it somewhere, which can later be leaked. The password can easily be stolen online by using phishing sites and can be stolen with keyloggers. We can create a strong password by using long characters, but it poses a risk of being stolen by a recording camera, social engineering and the method mentioned above. There is a huge chance of a password being leaked by human error.
Biometrics is considered a secure authentication method than password and it is quite popular these days. We have lots of devices with fingerprint, iris scanner and face recognition for the identity management. Although it is secure than traditional pin or password it is not 100% foolproof. Fingerprint has already been spoofed by creating 3D printed fingerprints. Also, the face ID by Apple on iPhone X was also bypassed. One of the biggest disadvantages of biometrics is that it will last for a lifetime. For example, if someone created a fake fingerprint of our finger then it will be the same for forever and the attacker can get access anytime using our fingerprint.
Two-factor authentication is being widely used these days by lots of corporates. Since it requires multiple credentials for the authorization is considered more secure. If one of the credentials is leaked, then the attacker will not be able to gain access to the system due to the need of multiple authentications. Although it seems more secure, it has some limitations. A most common method of 2fa is to send the code over SMS and SMS message are notoriously insecure. A potential attacker can sniff the message and can read the authentication code.
Social media login
Most of the websites these days have adopted social media login. Users can log in on the websites by using their social media accounts like Google, Facebook, Twitter, Instagram etc. It is very easy for the user to login with social media accounts because they don't have to create a separate account for each site and they can log in on multiple sites with single social media accounts. If the social media account of the user is compromised, then the attacker can get access on all the sites that user had created an account using that social media account. Therefore, it is not considered that secure.
Most of the authentication method that we use these days are not secure and the credentials can be easily stolen with social engineering, phishing, and brute force attack.