What is Secure Software Development Life Cycle & Why it Matters

In today’s digital environment, securing your software or applications from potential cyber-attacks is on top of the priority list. Software developers are increasingly adopting cloud deployments, and this comes with lots of security concerns. To mitigate these potential issues, there’s a need to make security a critical element that cuts across the entire software development life cycle.

This is where the secure software development life cycle (SDLC) comes in to address security vulnerabilities early enough in the concept and design stages. A secure SDLC follows a long-term security-first approach to software development where every phase is thoroughly screened to minimize threats, with insights and expertise from a trusted software development company.

1. Why is a Secure SDLC Important?

The digital transformation age is full of new tech advancements that guarantee efficient processes and cost-saving opportunities for companies of all sizes. The shift to the cloud, for instance, is now mainstream, and several businesses are halfway in their transition. And while moving legacy systems to the cloud is a good thing, it comes with several security risks. So, organizations that are not prepared to face such risks are probably on a compromised edge. 

That said, a secure SDLC plays a central role in the implementation of robust application security. It seeks to maintain safe and secure operations from the conceptualization stage to deployment and maintenance. The benefit is that it becomes easier to spot security threats and to resolve them before they wreak havoc.

Thanks to already-developed functionalities available in various open-source components, most software developers do not have to code from scratch. This saves time as it allows developers to focus on building more innovative projects instead of reinventing the wheel. The problem is that the open-source database is more vulnerable to security issues, especially if it’s not well-maintained.

Therefore, a secure SDLC allows developers to run through security scans on open-source components before adopting them for use in their projects. A secure SDLC also empowers the development team to prioritize security and to continually integrate new measures into the process as they proceed. 

2. How Does Secure SDLC Work? 

The secure software development life cycle consists of five key phases, where each plays a critical role in enhancing the security of the overall software or application. These phases include:

2.1. Collecting Requirements

Here, key security concerns are gathered from all the stakeholders. For instance, security requirements such as ensuring personal information are only visible to the users. Another would be functional requirements, e.g., ensuring that users can easily verify and edit their data inside the app or software.  

2.2. Design Phase 

The requirements obtained in phase one are now used to blueprint what needs to be done and what needs to be avoided. In other words, functional requirements are translated into functional design concepts and security requirements into security design concerns. Security design is often approached from the lens of what should happen and what shouldn’t happen. This helps exhaust all the security requirements and concerns before moving to the development phase.

2.3. Development Phase 

This is the implementation phase, where the code is written or retrieved from open-source platforms to solve the problem in question. Often, secure coding guidelines are used to eliminate vulnerabilities that would be introduced into the development phase. Some of these guidelines include:

• Checking all the open-source libraries for security vulnerabilities before adopting them. Software Composition Analysis tools are often used.
• Validating all the user inputs prior to processing any data they hold.
• Verifying any data sent back to the user from the database.

2.4. Verification Phase 

At this phase, the software goes through the rigorous testing cycle to check for any security issues that might have sneaked in somewhere along the development stage. Due to the complexity of the code, it’s recommended to use automated testing technologies. These include tools such as CI/CD pipeline deployment for seamless software delivery.  

2.5. Maintenance and Evolution 

Once the verification phase is over and there are no vulnerabilities, the software is ready for release. However, this doesn’t mean that security testing is no longer relevant. In fact, vulnerabilities can slip into the system just after deployment; hence maintenance and evolution should always follow a security-first approach.

During this stage, any vulnerabilities found should be traced to the source to help uncover other underlying issues. At times, this would mean rewriting the application functionality and rethinking the use of open source components in future projects.

3. Popular SDLC Models in the Market 

Over the years, developers have relied on some secure software development lifecycle models to ensure their projects can withstand security threats. Some of the popular models include:

• The Waterfall Model – this is a documentation-intensive model that’s widely accepted and used in the software development niche. Here, the software development process is grouped into different phases. The waterfall model follows a structure where the output of one stage is the input of the following stage. So earlier phases often determine the processes and techniques to be deployed in the next phase.
• The Spiral Model – this is a risk-driven model with four main phases; planning, design, development, and evaluation. The spiral model emphasizes managing risks, so the project passes through these four phases repeatedly in an incremental and spiral manner.
• The Agile Model – this model adopts an iterative approach to development where each incremental part prioritizes testing and troubleshooting. 
• Often, the entire project is grouped into incremental builds designed in iterations, and where the iterations last for one to three weeks.
• Incremental model – here, the requirements are bundled at the start of the project before they are divided into standalone modules, where each module goes through the five phases of secure SDLC. 
• The V-Model – with this model, the SDLC phases are planned in parallel. Execution happens sequentially in a V-shape, with each development phase paired with a testing phase in parallel.   

4. How to Succeed With Secure SDLC Implementation 

To make the most significant impact with your secure SDLC implementation, you should develop a comprehensive strategy with the end results in mind. Some of the critical steps include performing a gap analysis and creating a software security plan by establishing realistic goals with well-defined success metrics. 

But first, you’ll need to educate yourself and your co-workers/employees on the best coding practices and security frameworks. Conducting a thorough security awareness routine at the beginning will help educate all involved on the basics of software security risks and how to handle potential threats before getting started with the implementation process. 

Similarly, use the best security tools and technologies you can get your hands on. Checking for security vulnerabilities in huge texts of code requires more than just quick security scans. You need a comprehensive yet customizable cybersecurity tool with easy-to-understand security reporting metrics and insights. That way, you can successfully run a cybersecurity risk assessment before proceeding to develop the software.

5. Make Security a Top Priority 

Building a successful software that’s secure and scalable is a lot of work. There are numerous security and functionality concerns that go into the equation. But with a competent team and the right set of tools and technologies, it’s possible to transcend all the security obstacles and develop a robust application that meets and exceeds market standards. However, achieving this milestone calls for keen attention to security aspects in every phase of the software development journey.