Your PHP site is launched. Congratulations! But wait.. did you take care of essential security hardening?
PHP is a lightweight yet very powerful backend programming language. It powers around 80% of the global web applications, making it one of the most commonly used languages in the development world.
The reason for its popularity and wide usage is its easy coding structure and developer-friendly functions. There are a lot of CMS and frameworks built on top of PHP and thousands of known developers from all around the world are a regular part of its community.
One great example is WordPress.
When PHP applications are deployed on live servers, it may face several instances of hacking and web attacks, which makes its site data extremely vulnerable to get stolen. It is one of the most debated topics in the community, that how to build a completely secure application, keeping in check all the core objectives of the project.
Despite their best efforts, developers always stay wary of the hidden loopholes that go unnoticed while developing an application. These loopholes can seriously compromise the protection of vital site data on any web hosting for PHP MySQL apps, leaving them vulnerable for hacking attempts.
So, this article is all about some useful PHP security tips that you could use wisely in your projects. Using these little tips, you can make sure that your application always stands high on security checks and never gets compromised by any external web attacks.
Cross-Site Scripting (XSS)
Cross-Site Scripting is one of the most dangerous external attacks performed by injecting any malicious code or script into the website. It can affect the cores of your application, as the hacker can inject any type of code into your application without even giving you a hint. This attack mostly occurs in those websites that admit and submit user data.
In an XSS attack, the injected code replaces the original code of your website, yet works as an actual code disrupting site performance and often stealing the data. The hackers bypass the access control of your application, getting access to your cookies, sessions, history, and other vital functions.
You can counter this attack by using HTML special chars & ENT_QUOTES in your application codes. Using ENT_QUOTES, you can remove single and double quote options, that allows you to purge out any possibility of the cross-site scripting attack.
Cross-Site Request Forgery (CSRF)
CSRF hands out complete application control to the hackers to perform any undesirable action. With complete control, hackers can carry out malicious operations by transferring infected code to your website, resulting in data theft, functional modifications, etc. The attack forces the users to change the conventional requests to the altered destructive ones, like transferring funds unknowingly, deleting the entire database without any notification, etc.
The CSRF attack can only be initiated once you click on the disguised malicious link sent by the hacker. This means that if you are smart enough to figure out the infected hidden scripts, you can easily rule out any potential CSRF attack. Meanwhile, you can also use two protective measures to fortify your app security, i.e. by using the GET requests in your URL and ensuring the non-GET requests only generate from your client-side code.
Session hijacking is an attack through which the hacker steals your session ID to gain access to the intended account. Using that session ID, the hacker can validate your session by sending a request to the server, where a $_SESSION array validates its uptime without keeping in your knowledge. It can be performed through an XSS attack or by accessing the data where the session data is stored.
To prevent session hijacking, always bind your sessions to your actual IP address. This practice helps you to invalidate sessions whenever an unknown violation occurs, immediately letting you know that someone is trying to bypass your session to get the access control of the application. And always remember, not to expose IDs under any circumstances, as it can later compromise your identity with another attack.
Prevent SQL Injection Attacks
The database is one of the key components of an application that mostly gets targeted by hackers via an SQL injection attack. It is a type of attack in which the hacker uses particular URL parameters to get access to the database. The attack can also be made by using web form fields, where the hacker can alter data that you are passing through queries. By altering those fields and queries, the hacker can get control of your database and can perform several disastrous manipulations, including deleting the entire application database.
To prevent SQL injection attacks, it is always advised to use parameterized queries. This PDO queries properly substitute the arguments before running the SQL query, effectively ruling out any possibility of a SQL injection attack. This practice not only helps you to secure your SQL queries but also makes them structured for efficient processing.
Always Use SSL Certificates
To get end-to-end secured data transmission over the internet, always use SSL certificates in your applications. It is a globally recognized standard protocol known as Hypertext Transfer Protocol (HTTPS) to transmit data between the servers securely. Using an SSL certificate, your application gets the secure data transfer pathway, which almost makes it impossible for hackers to intrude on your servers.
All the major web browsers like Google Chrome, Safari, Firefox, Opera, and others recommend using an SSL certificate, as it provides an encrypted protocol to transmit, receive, and decrypt data over the internet.
Hide Files from the Browser
There is a specific directory structure in the micro PHP frameworks, which ensures the storage of important framework files like controllers, models, the configuration file (.yaml), etc.
Most of the time, these files aren’t processed by the browser, yet they are kept being seen in the browser for a longer period, building a security breach for the application.
So, always store your files in a public folder, rather than keeping them in the root directory. This will make them less accessible in the browser and will hide the functionalities from any potential attacker.
PHP applications are always vulnerable to external attacks, but using the tips mentioned above, you can easily secure the cores of your application from any malicious attack. Being a developer, it is your responsibility to safeguard the data of your website and make it error-free.
Besides these tips, many techniques can help you secure your web application from external attacks, like using the best cloud hosting solution that ensures you have optimum security features, cloud WAF, document root setup, whitelisting IP addresses, and more.