Secure Coding Best Practices Every Developer Should Know
Code is the core of a computer program; if there are any vulnerabilities in it, then the whole program may be compromised by cyberattacks.
The continuously expanding number of security breaches that have occurred over the past few years is too alarming to ignore. In recent years, we have learned that cyber attacks have exposed millions of people's financial and personal information.
Major tech companies like Google, Apple, and Red Hat have reported vulnerabilities in their respective operating systems and software. These vulnerabilities have made it essential to maintain the quality and security of code more than ever before.
So, in this article, we will learn all about secure coding and its best practices.
What is Secure Coding?
Secure coding is the practice in which any software is developed in a way that protects accidental security vulnerabilities. It governs the coding techniques, practices, and decisions that developers make during the development. Secure coding’s core aim is to ensure that the written code can minimize any vulnerabilities. It involves writing code in a high-level language that adheres to strict principles of security.
Secure coding is much more than just writing, compiling, running, and releasing code into the production environment. To completely embrace secure coding, you must also create a secure development environment that is built on secure and reliable infrastructure using secured software, services, and providers. Besides, the code must not have any logic flaws, bugs, errors, and defects that can form security risks.
There are multiple secure coding standards and security guidelines for coding that are widely accepted and used today. Some of these standards are SEI CERT Coding Practices, UC Berkeley Security Policy, and Open Web Application Security Project (OWASP) Coding Practices.
Why Use Secure Coding Techniques?
When it comes to application security, even the silliest mistake can create security risks. Media reports have highlighted the insecurities in the software that is being used by us. Even the major brands and organizations equipped with the right knowledge and resources have suffered from different cyber attacks.
The goal of software security is to maintain the integrity, confidentiality, and availability of information resources to establish successful business operations that can only be achieved by integrating security practices.
Flaws in security can happen at any stage of the development lifecycle, like:
Failure to identify requirements of security upfront.
Errors in conceptual designs.
Technical vulnerabilities are introduced due to poor coding practices.
Implementing the software improperly or introducing errors during maintenance or updates
However, secure coding techniques make it easier for developers to remove common vulnerabilities by following security standards for coding. It also helps in weeding out exploited risks, preventing cyberattacks and leaks of sensitive information.
That’s the reason why secure coding’s fundamental part is understanding when external code should be integrated and when one should write the code by themselves. Moreover, every development environment should have a set of secured, trusted, and updated components for common tasks in the application development process.
It is best to consider security from the start of the project, as it is difficult to implement security controls later on in the development process.
Top Secure Coding Checklist
As complex security processes can create inconsistent results, for securing the application code, keeping the entire process simple is the key. Aside from that, don't reinvent the wheel when it comes to security.
In the year 2018, the OWASP foundation published its list of top 10 proactive security controls and then released its application security verification standard to establish both functional and non-functional controls of security at the time of designing, developing, and testing stages.
So here is the list of the top secure coding checklist that you should consider when developing your secured application.
For input validation, you need to conduct data validation on the authenticated server, determine trusted and untrustworthy data sources, specify accurate character sets and encode data into common characters before validating. In case of input rejection, there must be a validation failure.
Another important factor to maintain the security of the code is authentication. It is crucial to authenticate all the pages as well as resources and enforce the authentication system on a trusted system. After that, you can easily establish and use standard authentication services.
Another important thing to consider while authenticating is to segregate authentication logic from the resource that is being requested. If the app you are going to develop has a credential store to manage, it should ensure that the passwords are stored cryptographically to enhance security. Only use HTTP POST requests to transfer authentication credentials.
When it comes to passwords, they should be concealed on the user’s screen, and if someone is trying to access the account with the wrong credentials the account should be disabled for a certain time period to discourage brute force of password guessing.
Temporary passwords should have a short expiration time and users must be verified in case of password reset. You can also add multi-factor authentication for highly sensitive or transactional accounts.
While developing an app you should restrict access to protected URLs, functions, services, object references, application data, user and data attributes, and security configurations to authorized users only. Moreover, the app should deny all access if the security configuration information cannot be accessed.
Most software errors are caused by bugs, which can lead to vulnerabilities. Keeping a log of errors and handling them accordingly are two of the best ways to minimize their impact. Error handling attempts to prevent catastrophic failures by identifying errors in the code before they occur. Using error logging, developers can diagnose errors and mitigate their effects. To comply with secure coding standards, it is necessary to document and log all errors, exceptions, and failures.
To improve data protection, you should encrypt highly sensitive information on the server-side by using cryptographic hashes and protect server-side code from being downloaded by the user. Disabling the auto-complete feature on forms containing sensitive information can also help in enhancing security.
Implement encryption for sensitive data transmission by incorporating Transport Layer Security (TLS) certificates.
System configuration can be secured if you are using the latest versions of frameworks, servers, and other system components, or removing unnecessary files, functionalities, test codes, etc, from HTTP response headers.
Provide access to only authorized development and test groups and isolate development environments from the production network. Development environments are seldom as secure as production environments, which enables attackers to identify shared vulnerabilities or exploit them. It is thus imperative that you implement a software change control system to manage and track changes in both production and development environments.
For database security, use strongly typed queries, use input and output validation and use secure credentials to access the database. You should also change or remove the default passwords of the database with strong passwords or multi-factor authentication.
General Coding Practices
Now that we have gone through the checklist of secure coding, it is time to have a look at general coding practices that any developer should follow:
Always use tested and approved codes rather than unmanageable code.
Do not allow the app to directly issue commands to the operating system using initiated command shells instead use task specified APIs that conduct tasks related to the OS.
To verify the integrity of libraries, interpreted codes, configuration files, and executables use hashes or checksums.
Protect shared resources and variables from ill-suited intersecting access.
Don’t pass user-provided data to a dynamic function.
Users should not be able to alter existing code or develop new ones.
Review all third-party code, applications, and libraries to ensure safe functionality and business necessity.
Use cryptographic signatures for code in case of automatic updates and determine signature verification by clients.
Software has become an essential part of our day-to-day lifestyle, hence the security and integrity of the underlying code are critical. All the secure coding best practices that we have discussed here are already familiar to experienced programmers.
So if you too will learn the common secure coding standards and techniques you can easily reduce the number of attacks on the software by delivering a secure and reliable end product.