It’s not a secret that reaching any goal is easier when you have a clearly outlined plan. Knowing what exactly you are going to do and in what order gets you at least halfway on the road to success. This is especially true when it comes to such a complicated and multifaceted process as software development. If you strive to implement a workflow that is well-structured, iterative, and systematic, your web or mobile application development process becomes more efficient, transparent, and cost-effective.
The most widespread approach for structuring and organizing the software development process is known as the software development life cycle (SDLC). Different SDLC models are implemented in the vast majority of software development companies around the globe. However, the SDLC process itself is quite complex, so if you don’t pay attention to certain aspects it may lead to adverse results and cause more problems than it solves. One of the most important aspects that can heavily impact the success of the SDLC, in general, is, no doubt, security.
So what should you know about the secure software development life cycle and how to ensure it is successful? We have prepared some useful information to help you better understand the software development life cycle itself and showcase the most popular secure SDLC best practices.
What is the software development life cycle?
The SDLC is a concept that is typically used to describe the complete software development process from the beginning to the end. The SDLC typically consists of seven stages, although the whole development process can look slightly different depending on the exact SDLC model that your development team adopts (waterfall, Agile, DevOps, etc.). Even the number of steps can change as stages are sometimes combined or, vice versa, broken into smaller parts, but the activities involved and their order remain more or less the same. Let's take a closer look at each SDLC stage:
- Planning: this is the stage where you prepare the foundation of your software development project. It usually involves outlining the scope of work, required resources, budget, the timeframe for the project, and so on.
- Analysis: now is the time to gather and clarify the requirements for the software or feature you are about to develop. It is important to make sure your development team understands the requirements clearly.
- Design: this phase involves some more practical work on the look and feel of the future software. Before you start coding, you need to think about the interface layout, which often involves creating mockups or even a prototype.
- Development: the actual coding starts only at this stage in your development life cycle.
- Testing: when the source code is ready, it is time to check it for bugs and fix the issues that you discover.
- Deployment: once you are sure your code is safe, you deploy it into a production environment.
- Maintenance: after the production release, you don't give up on your software. It has to be monitored, maintained, and updated as necessary.
SDLC benefits
The SDLC represents a comprehensive guideline that makes the life of development teams and project managers easier. Its methodology allows you not just to set clear goals but also to make sure development teams follow through and develop code according to the detailed requirements.
The whole software development process becomes faster when the SDLC is adopted because it allows you to standardize the entire workflow, including code reviews and security checks. With no unnecessary back-and-forth requests, developers save time and can collaborate, coordinate, and create software more efficiently, ensuring the high code quality of the deliverables.
The planning improvements that the SDLC provides also mean resource usage becomes optimal, potentially leading to significant savings. Maximizing the quality and minimizing delays with new builds makes customers happy, but lowering the costs ensures all other stakeholders are satisfied too.
Why do you need a secure SDLC?
Security risks can appear at any stage of the software development life cycle, and it has long been proven that the earlier you catch a potential problem, the cheaper it will be to fix it. But that is not the only reason why security considerations should be at the top of your list when you work on any software solution.
If you don't identify security flaws in time and release software with security vulnerabilities, it puts all your end users at risk. If application security is lacking, customers may lose incredibly valuable data, which could lead to hefty fines and even a complete loss of your business reputation.
Furthermore, a secure software development life cycle provides the tools that make regulatory compliance with security requirements in certain industries an achievable goal. When you can show your customers that your software follows specific security guidelines, it increases its attractiveness and revenue and, of course, customer satisfaction too.
Learn more about the importance of a secure software development life cycle (SSDLC).
Secure SDLC best practices
There is no official list of best practices that you must adhere to when you create secure applications, but our experience in software projects has allowed us to gather and recommend the most effective ones when it comes to preventing security issues and addressing security concerns.
Clear security requirements
When you work with your security and development teams on defining the goals and requirements that apply to your software development projects, it is crucial to remember it is not a one-off process. Security threats keep evolving, so you must keep your requirements up to date. This should be a continuous process of updating security risk documentation and reviewing potential risks, while also keeping appropriate people and organizations informed about the current set of requirements.
Secure design
Using the software design requirements to facilitate the standardization of security practices is one of the most effective secure SDLC best practices. Your code design requirements should facilitate continuous improvement with regard to integrating security. By pointing out specific tools and best practices for application security and the exact points when to use them in the software development life cycle, you help your development teams integrate security into the process of building software.
Threat modeling
Another best practice to include at an early development stage in any project is threat modeling. This involves a detailed analysis of the software architecture to predict potential vulnerabilities, their severity, and their location before the application is fully developed. This also helps to proactively tackle security issues before they become serious business risks.
Educating your development team
It pays to improve security awareness in your software development teams. Educating your developers on secure coding practices, frameworks, and security tools through dedicated training sessions leads to an overall improvement in security quality. Make sure your team stays on top of ongoing attack trends and understands the consequences of developing insecure code.
DevSecOps
Knowing how to make secure code is important, but if you want to improve quality assurance and solve security issues across your organization, it will require shifting the whole mindset of your teams towards implementing security beyond the code. The strategy of integrating security into every single stage of the software development life cycle is known as DevSecOps. It presupposes that your security team won't be the only one working on making your application secure. Everyone who is involved with the project should strive for continuous improvement of application security.
DevOps practices in general can facilitate faster development and better quality for your software. Adopting DevSecOps is how you proactively improve security. When you start adding security checks as early as possible, a lot of threats become preventable long before there could be any significant damage.
Code review
Among SDLC best practices is carrying out code reviews as standard. Code reviews improve the overall code quality, help to gather important feedback, and make sure that your code repository is free from bugs. Implementing code reviews is something you can do no matter which SDLC model you prefer. Whether you use an Agile methodology on your project or have a dedicated code review team, this practice is an efficient practical approach for detecting deviations from secure coding practices and vulnerabilities in the code.
It might appear that code reviews are time-consuming but if you organize the process well and choose the right tools, it can become a natural and streamlined part of your process. To guide your teams through a code review, it helps to design a checklist that all team members will use when they go through the review procedure. Furthermore, using special tools for static analysis security testing that check your source code with the help of AI and semantic analysis prevents human errors and ensures secure code.
Testing
Quality assurance is an important part of secure software development. It is crucial to pay special attention to all security testing procedures, from unit testing to integration testing, and not rely solely on automated testing. Certain critical application features or business logic sometimes need manual security tests to ensure their resilience against potential attackers.
Moreover, you can extend your code review practice by having a security expert perform penetration testing. A practical risk management approach, penetration testing is typically performed by a specialist who imitates an attack on the application, thus discovering its security issues or vulnerabilities before a genuine malicious attack. While code reviews happen at earlier stages of application development, penetration testing is typically used to address security risks in the later stages of the SDLC process.
Open source components usage
Open source components are used in applications by the vast majority of software development companies. They have a lot of advantages, being customizable, diverse, and, of course, either completely free or comparatively cheap. Using open source components in your software architecture can increase development speed and optimize resource usage. But open source security management has to be something your security and development teams work on very carefully. Open source code (like any other code) can have security flaws that can become real security threats to your application.
If you decide your team needs certain third-party components with open code, it is recommended to check them for vulnerabilities. There are various analysis options for open source components, such as code analyzers or automated tools for software composition analysis that even provide automatic patches and insights for remediation.
Access control
Modern Agile SDLC methodologies promote faster development and constant improvement of the software's new and existing features by providing the tools to update the source code in the project repository almost instantaneously, perform automated testing, and so on. While DevOps practices like continuous integration and deployment have lots of benefits for end users, the complex tools used for automating these processes also open up possibilities for cyberattacks due to human errors like incorrectly configured settings or permissions.
Paying special attention to who has access to code repositories seems obvious but is, in fact, an integral part of ensuring secure software development on your project. Someone with unauthorized access to the source code repository can disrupt the SDLC process and damage the results of many weeks or even months of your team's work.
Response plan
Even the best efforts to establish proactive security measures can't prevent 100% of security issues. That is why your secure SDLC risk management process should include planning what to do if a problem happens after all. If a security breach occurs, there will be no time to think about the next steps, so everyone should already know the mitigation plan and their roles in it.
It is best to designate a special task force and instruct the members of that team on their responsibilities before something happens. Your team should be prepared for what might happen, so running trials with mock emergencies will be helpful. And to make sure your response and recovery plan is flawless, ensure your security testing includes disaster recovery testing. It is recommended to continuously review and improve your plan as part of your secure SDLC so that it is as robust and effective as possible.
Security audits
Your internal security team might be very good, but SDLC best practices for risk assessment suggest involving external experts can bring a fresh perspective that sometimes helps identify security flaws that are far from obvious. Moreover, scheduling regular security audits helps to get a closer look at your overall risk management procedures and identify security gaps.
Obviously, a security audit isn't something that should happen too often since it is a very thorough process which can also be pretty expensive in the case of an external audit. But if your goal is a truly secure SDLC, then this is a way to go that extra mile. Involving third-party experts can raise your application security to a high level that might be unreachable if you limit your secure SDLC process to only security testing, for example.
Conclusion
If you follow these recommendations, you will find that your software developers can code high-quality software and do so without compromising security. No matter which SDLC model you choose to adopt, integrating security is the staple you need if you want your SDLC to be a success. Secure SDLC best practices are a way to guarantee your released software won't become a danger to your own or someone else's business.
