Today we are going to discuss input vulnerabilities in web applications. Input vulnerabilities are typically vulnerabilities that arise in web applications or websites. Among these, SQL Injection, Cross-site scripting, and other similar vulnerabilities are at the top. If an attacker finds any input vulnerabilities on your website, they can compromise your website’s security. The attacker can dump your database data, manipulate your users, and perform various malicious actions on your website. Therefore, input vulnerabilities are the most important vulnerabilities in web applications or websites. Finding and fixing them is the responsibility of either a pen-tester or a developer. These vulnerabilities arise when a developer fails to validate input functions correctly or enable sanitization. This makes it easier for attackers to exploit them.

If an attacker can exploit input vulnerabilities, then performing an attack becomes easier for them. We can explore input vulnerabilities on three levels: basic, intermediate, and advanced.

Basic level

At the basic level, a developer should enable input validation. If a developer begins to validate input properly at the basic level, it will become difficult for an attacker to perform an attack. It is not enough to stop an attacker, but using security features like input validation is necessary to stop an attacker. If an attacker tries to use a payload like cross-site scripting or SQL injection, the server will block them or give a warning message that they are attempting a malicious input.

Intermediate Level

If we look at input vulnerabilities at the intermediate level, a developer uses input filtering and sanitization to stop an attacker. In input filtering, the user or attacker’s input query is filtered first. Then, it is tested to see if the input that the user requested is allowed or not. If the input is malicious, then it is sanitized by encoding it so that it behaves like a normal query and not as a command. At the intermediate level, both of these security features are used to frustrate the attacker, and they may fail in most of their attacks.

Advanced Level

At the advanced level, an attacker uses advanced input validation or sanitization techniques to protect themselves from input vulnerabilities. The attacker tries to use these techniques to protect themselves from high-level vulnerabilities such as SQL injection and cross-site scripting. In these vulnerabilities, the developer’s attention is drawn to regular expressions, parameterized queries, and the developer secures them so that no attacker can breach site security through these attacks.

SQL Injection

SQL Injection is the most significant cyber attack that can be performed against any web application. In this attack, an attacker tries to breach the website’s security by using malicious queries and gain access to the database on the application layer. If an attacker succeeds in doing so, they can dump the entire database and misuse the users’ important information. If an attacker targets a shopping site and successfully dumps the database through SQL injection vulnerabilities, they can use all the credit card details of the users, which is a very dangerous thing.

There are many types of SQL injection vulnerabilities, such as time-based SQL injection, blind SQL injection, and simple SQL injection. An attacker injects malicious queries into user inputs or parameters to break the application and continue their attack.

OS Command Injection

We have another important vulnerability in input vulnerabilities called OS Command Injection, which is the most dangerous vulnerability we have. In this vulnerability, an attacker tries to execute their malicious commands directly on the server. If the developer has not properly configured the server side, then an attacker can easily succeed in their attack. An attacker can read and view server files. Additionally, they can drop their backdoor on the server, establish a reverse connection, and compromise the entire server. This can lead to the attacker scanning and exploiting all devices connected to the internal network. Even with low privileges, an attacker can easily compromise the web server on which the website is hosted.

Cross-Site Scripting (XSS)

We have another important input vulnerability known as Cross-Site Scripting (XSS). In this vulnerability, an attacker attempts to compromise security by using a crafted payload. XSS vulnerabilities are mostly found in input functions or parameters, and an attacker inserts their payload using these functions or parameters. If their payload is triggered, an XSS popup will appear. There are three types of Cross-Site Scripting (XSS) vulnerabilities: reflected-based XSS, stored-based XSS, and DOM-based XSS.

checkout our other articles : 5 Essential Tips to Keep Your Facebook ID Secure