Sunday 22 September 2019

Web Security Best Practices for PHP

Cyber crime has been on the increase for decades now, hence the need to ensure that your PHP code is totally secure. There are best practices that are recommended for programmers who want to protect their code from malicious attacks. Some of the important tips and tricks are enumerated in this article to ensure that your application is less vulnerable and without performance issues.

#1 Validate Input Data

There is a lot to do while writing PHP code to ensure that your web application is not easily exploited by certain users. Proper data validation will ensure that your application is protected from the activities of hackers and spammers who have illegitimate motives.

Client-side or server-side validation could be used to guard against problems that come with bad input from a user. Data validation with JavaScript which happens on the client-side is a lot faster with fewer traffic calls. The downside is that it is dependent on the browser, and disabling JavaScript will make your application vulnerable.

Server-side validation, on the other hand, is a lot slower due to several traffic calls, but cannot be manipulated by spammers. Have you ever tried to pick a username while creating a new social media account and got a response stating that it is already taken? That is server-side validation at work.

Validating all forms of data regardless of its source using both techniques is key to ensuring that your app works in the best way possible.

#2 Prevent Cross-Site Scripting (XSS)

Cross-site scripting (XSS) occurs when a user injects code into a web page to bypass certain restrictions. The code which is usually in JavaScript eventually runs on the server and can expose sensitive data of other users.

Web application vulnerabilities like XSS makes it possible for code from untrusted sources to be executed in the victim's browser as a result of poor data validation. Filtering all entries and eliminating special character with functions like stripslashes(), htmlspecialchars(), and trim(). Eliminating tags that would make the malicious code valid ensures that users are not redirected to a different server, keeping their private data protected.

#3 Routine PHP Updates

PHP updates come with security fixes which ensures that your web applications are not easily compromised. Endeavor to update all your sites to the latest PHP version to ensure that there are no bugs and other vulnerability issues.

Running older versions of PHP will have you using deprecated functions which are no longer supported, causing your site to malfunction. These functions are interpreted wrongly, thereby opening loopholes for the exploitation of your code by attackers.

There are a couple of tools that can be used to check for deprecation in your code so that you do not have to update the entire code. PHP Analyzer (Phan) and PHP 7 Migration Assistant Report (MAR) are some powerful tools that check your code line by line for compatibility issues.

#4 Eliminate Session Hijacking Risks

While using a web application, core data is collected during the session which should be stored in a secure location. It is usually saved to a file and is not very efficient as hackers can easily access the entire information contained therein.

Although encrypting session data could work but is not entirely efficient. Storing your data on a database is recommended, ensuring that it is totally safe and easily accessible from different machines. The session_set_save_handler() function lets you control the way that the session data is stored.

#5 Limit File Access

PHP projects feature several files that contain important data which are relevant to the web application. The fact that some of these files do not bear the “.php” extension means that they would not be parsed even when called directly.

However, files that contain sensitive application data should be kept in directories that are not accessible to the end-users. These PHP include files should also be saved in ".php" extension to ensure that everything works perfectly.


Developers all over the world are in a race against time to fix security loopholes in their applications to avoid malicious attacks that could victimize end users. There are several other strategies to ensure that your PHP applications are impenetrable even for skilled hackers. Hence, you need to keep developing yourself as hackers are getting better as well.


Author Bio:

Cynthia Young loves taking every opportunity to share her knowledge with others. Along with digital marketing, Cynthia is also passionate about personal growth and wellness. When she isn’t writing, she can be found hiking with her dog, cooking Thai cuisine, and enjoying hi-tech thrillers. She also frequently writes articles on the company The Word Point translation service.