What is Secure Coding and Why is It Important?

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Summary: What is Secure Coding and Why is It Important?

Most vulnerabilities stem from an application or program’s source code. Flaws or errors in a program’s code can be exploited easily by malicious users to take control of the program and use it for their own personal gain.

Luckily, most common software security vulnerabilities can be mitigated by following well-established secure coding standards, such as OWASP and SEI Cert. Some of the most essential components of secure coding are:

1. Data input validation
2. Authentication and Password Management
3. Access Control
4. Keep it Simple
5. Cryptographic Practices
6. Error Handling and Logging
7. Data Protection
8. Threat Modeling

Learn more about secure coding in the article below!

Security vulnerability exploits show us just how vulnerable software code really can be. Software code sits at the heart of how your application works. If your code has security vulnerabilities, your entire app might be vulnerable to cyberattacks.

A quick glance at tech headlines over the past year reveals how often security vulnerabilities in software are exploited by unauthorized users.

Two big-tech companies, Apple and Google, reported vulnerabilities in their respective operating systems. Even Red Hat, an IBM subsidiary that provides open-source software, reported a vulnerability in its Linux Enterprise version that is being actively exploited.

Preventing cybersecurity incidents, which can cause leaks of sensitive data and other personal information, starts at the very beginning of the software development process with the source code itself. In this article, we go over what secure coding is, why it’s important, and what the top secure coding practices are.

What is Secure Coding? Why is Secure Coding Important?

Coding, or computer programming, is the practice of designing executable programs in a language that can be interpreted by your computer. When a software developer writes this source code, they need to consider many things, such as:

• Architecture and design requirements of the application
• Code optimization and efficiency
• Code security and safety

Secure coding makes it easier for developers and programmers to weed out common vulnerabilities in their software by following certain best practices and guidelines, known as secure coding standards.

The adoption of secure coding practices is important because it removes commonly exploited software vulnerabilities and prevents cyberattacks from happening. Moreover, optimizing for security from the start helps reduce long-term costs which may arise if an exploit results in the leak of sensitive information of users.

Despite the importance of coding in a secure manner, software vulnerabilities are rampant. A search using the National Institute of Standards and Technology (NIST) vulnerability list shows that there have been 40,569 application vulnerabilities in the last three years alone.

We’ve listed some of the best secure coding practices below in an attempt to reduce software vulnerability and make computer programs safer for everyone!

How Do You Code Securely?

There is abundant literature on secure coding best practices. For example, The Open Web Application Security Project (OWASP) has created a set of guidelines that help developers mitigate common software security vulnerabilities. Similarly, the SEI CERT secure coding standards lay down ten secure coding best practices that programmers can incorporate to maximize application security.

We have distilled some of the most relevant practices from both these sources:

1. Data input validation

This covers numerous aspects of data source and input validation. Most threats to cybersecurity come from external data inputs in the form of cross-site scripting, buffer overflows, and injection attacks.

Hence, it is crucial to establish security practices that govern which sources are trusted and how data from untrusted sources will be verified.

2. Authentication and password management

Limiting access of the program to authorized users is an effective way to prevent cyber-attacks and data breaches. Some best practices for authentication and password management include:

• Using a trusted system for password hashing
• Enforcing password length and complexity requirements
• Storing authentication credentials on a trusted server
• Using multi-factor authentication

3. Access control

Access control goes hand in hand with authentication to ensure that a malicious user cannot easily gain access to the targeted system. As a general rule, it is best to adopt a default-deny approach, which means that users who cannot demonstrate authorization should be denied access. For web applications that entail extended log-in periods, the code should require periodic re-authorization for sustained access.

4. Keep it simple

While this may not be intuitive, keeping your code simple and clean is a great way of ensuring its security. This is because complex designs increase the likelihood that vulnerabilities will creep into the code. Developers should avoid unnecessary complexities while writing software and include only what is essential.

5. Cryptographic practices

The secure coding standards mentioned above stress the importance of implementing effective cryptographic processes to protect secrets from the application user. All random values generated as part of the cryptographic process should be generated using an approved random number generator to ensure that they are unguessable.

6. Error handling and logging

Even the most well-written code is likely to run into errors. What’s important is that when an error crops us, it is identified and dealt with at the earliest to contain its impact.

The accurate identification of errors depends on effective logging of all events that occur in the code. Developers can access these logs to diagnose any errors that may have arisen. But be careful not to include any sensitive information in the error messages or logs!

7. Data protection

The objective of most cyber attacks is to access sensitive data. Hence, it comes as no surprise that data protection is an important aspect of secure coding requirements. Some useful tips for effectively protecting data include:

• Adherence to the principle of least privilege, i.e. elements of the code should execute with the least set of privileges necessary to complete the job
• Regular deletion of temporary or cached copies of sensitive stored on the server
• Not storing passwords and connection strings in clear text or any non-encrypted manner on the client-side

8. Threat modeling

It’s difficult, if not impossible, to protect yourself against threats you aren’t aware of. This is why threat modeling is so important. It involves identifying potential threats and then defining countermeasures to prevent or mitigate them from occurring. A threat modeling exercise should be carried out on a regular basis to ensure that any new risks are not left out.

9. Beyond coding

Implementing the above guidelines should help weed most vulnerabilities that stem from the code itself. However, ensuring that your code is secure is an ongoing process and requires constant vigilance. Other areas that need to be part of a holistic approach to creating secure code include:

1. A system based on “least privilege”: Keeping access to any code on a need-to-know basis will help prevent any injection attacks. This can be particularly tricky when using outsourced developers or development companies.
2. Defense in depth: Keep on layering defensive strategies as the code gets promoted through to production. Make sure your runtime environments are as secure as your code.
3. Practice good quality assurance: Use various assurance programs such as code reviews and PEN testing to ensure quality.
4. Understand how to apply the Software Development Life Cycle (SDLC) to secure coding. Using an SDLC approach will help you to ensure that security filters through all parts of the development lifecycle.

Resources for Successful Secure Coding

Keeping your development team trained and in touch with the latest secure coding standards is crucial to secure coding. You can’t expect programmers to know how to code securely from the get-go. Instead, they need to be trained and made aware of the different secure coding practices, as well as the common security vulnerabilities.

Below are some useful resources to help you and your team on a path to creating secure code.

Secure Code for a Competitive Edge

Security starts with your code, and creating secure code is a vital part of creating a great software product.

Insecure coding practices not only leave your customers at risk, but they will impact the reputation of your company. Applying the tenets of the SEI CERT and OWASP secure coding guidelines is a good place to start. Producing demonstrably secure software can not only allow you to prevent cyber-attacks but give your organization a competitive edge.