Since the software development lifecycle gained prominence in the 1970s, it has undergone many modifications and tweaks. Over time, the development needs of end users are combined with the evolving nature of the challenge. The most obvious aspect is security – leading to the formation of different software development methodologies and approaches. One such approach is the Secure Software Development Life Cycle (SSDLC).
SSDLC emerged to address the growing security challenges facing application security. Incidents involving data breaches, privacy violations, and other cyber threats are so common in today’s society that any software development model that does not prioritize security is likely to result in financial and reputational losses for the development company.
Before getting into the SSDLC, let’s take a look at the SDLC approach.
What is the software development life cycle?
Software Development Life Cycle (SDLC) is a systematic and standardized approach to developing software applications. The SDLC borrows heavily from elements of the general project management lifecycle approach, evident in the similarity of the steps and phases involved.
While it is unlikely to find two companies applying exactly the same SDLC process, the main stages are common in most organizations.
Major stages of the SDLC process
In general, a typical SDLC process consists of five stages:
Requirements gathering: Each application is developed to solve some problem and provide utility for users. In gathering requirements, the development team’s goal is to understand the customer’s needs and goals and define the resources needed to best complete the project.
Design: At this stage, the foundation is laid for the whole project. Some of the main details identified here include the programming language, architecture, platform, user interface, communication protocol, and security.
Development/Build: This is the part where you put all your plans into action by developing the application source code and implementing all the functionality of the application, including the user interface and security.
Testing: One of the most important components of any SDLC process is testing software for bugs, errors, performance, and functionality. Any application performance issues discovered during this phase will usually be corrected prior to deployment.
Deployment and maintenance: Release the application for use by prospective clients. This usually involves getting the app approved by the App Store and making it available for download. Of course, highly specialized enterprise apps are often not released in the app Store, but are made available directly to customers.
Common software development lifecycle models
The SDLC process remains unchanged in most organizations. However, there is nothing in the software development rulebook that forces any developer to always follow the SDLC stages in one-dimensional order.
Over the years, organizations and strategists have experimented with different SDLC models to better meet customers’ changing needs. The most popular examples are as follows:
waterfall
The most straightforward of all models is the WATERFALL approach to the SDLC. In waterfall development, the phases of the entire development life cycle occur in a fixed order, from requirements gathering to final deployment.
V – model
The V model is a linear model.
The main feature of this model is its heavy emphasis on testing. This is why each phase of the V model has its own testing activity, so that testing takes place during all phases of development until completion.
The extensive testing and quality control embedded in the V model makes it one of the most expensive and demanding software development methodologies. Therefore, it is only used in highly specialized situations, such as projects with a low tolerance for risk of failure and error.
Iterative model
Iterative and incremental models are gaining more attention as organizations explore non-traditional and nonlinear ways of working. Developers can implement the model sequentially or in parallel.
In essence, the iterative model is cumulative, with new software modules and features added to each iteration.
The beauty of iterative models is that they allow adjustments at any stage of development, as long as the requirements change within the scope of the project.
The iterative model has proved most effective in large projects where the functionality of the application is loosely dependent.
Agile development
Today, agile development is the most widely used SDLC model. At its core, Agile follows an iterative development style with a greater emphasis on communication and early customer feedback.
Each iteration in the Agile model is designed to develop a complete module or function that can be reflected in the final version of the application. This means that the same sequence of steps in a traditional SDLC process is repeated many times until the project is complete, leading to repeated testing and quality assurance.
Frequent releases of agile guaranteed software and communication and feedback with customers make it a popular choice for most organizations.
Agile development is often adopted when:
Need early customer feedback on the launch plan.
Large projects that can be easily broken down into smaller parts, each part developed incrementally.
Need to add an “S” in SLDC
SSDLC is a natural evolution of SDLC, emerging in response to the increasing importance of security in modern application development environments.
In short, SSDLC provides a structured framework for application development aimed at enhancing security, integrating security elements into all phases of the SDLC.
In a world overrun with devices, gadgets and electronics, security breaches can spell disaster for individuals and organizations. In the case of a company, neglecting safety can lead to huge financial losses. Exploiting a single vulnerability can wreak havoc on an organization’s systems.
In the wake of serious data breaches and privacy scandals such as Facebook-Cambridge Analytica, the iCloud leak, and the NSA’s PRISM surveillance program, legislative frameworks such as the GDPR of the EU and the CCPA of the US require organizations to take data protection measures for the security of all relevant parties.
In this context, any software developer needs to make security a key consideration at every stage of the development life cycle.
SSLDC provides a solution to such security disasters, enabling organizations to minimize risk and significantly more effectively control their reputation and financial security. This is the main reason why companies adopt SSDLC.
SSDLC Best Practices
Let’s look at how these steps of the classic SDLC can be modified as you integrate security into each stage.
1. Requirements collection
The focus of this phase is now on preparing a list of safety and regulatory requirements, as well as other general details of the project. A detailed plan is generally developed to develop the appropriate security activities for all phases.
A key part of this phase is safety awareness training. Training courses are designed to provide project participants with security knowledge, enabling them to take steps for security design and development, and to establish security concepts for the entire team from the outset.
Design of 2.
The design phase is where all the details are determined, such as the programming language, software architecture, functionality, and user interface. The SSDLC practices at this stage involve identifying most of the application’s security functions and defense mechanisms.
Some security-focused security activities during this phase include:
Threat modeling: Simulate attack scenarios and integrate effective countermeasures into the list of identified threats that can compromise the application, thus laying the foundation for all subsequent security measures. Early detection of possible threats not only reduces the likelihood of a successful attack, but also reduces the costs associated with security integration across the project.
Design documentation and review: Modeling results help the team prepare design documents that identify security requirements and key vulnerabilities in application security that need to be addressed.
Identify third-party risks: If the associated third-party components are vulnerable, even the most secure applications can be vulnerable, making the entire system vulnerable. Therefore, it is important to check and monitor third-party applications for possible security vulnerabilities, and patch them if necessary to ensure the integrity of the entire application system.
3. Development/Build
In the context of SSDLC, this phase involves activities such as secure coding and scanning.
Secure coding: In this phase, you consider security best practices for application coding, such as authentication and encryption. Often, the team’s goal is to follow secure coding practices that successfully eliminate many basic vulnerabilities, minimizing the need to retrace the same steps to fix and patch bugs found later in the project.
SAST: The Static Application Scanning tool (SAST) helps applications complete prior testing and review of code. Static scanning helps find security problems at all stages of development, making it easier to detect and fix problems as the project progresses.
Manual code review: SAST provides automatic scanning. This saves developers a lot of time and effort in finding bugs and vulnerabilities in code, but still requires a human review to identify potential problems in code that could be exploited by malicious attackers.
4. Test
The testing stage is the stage of security testing. Common practices performed at this stage include:
Dynamic scanning: Unlike SAST, the Dynamic Application Scanning Tool (DAST) simulates hacking attempts and threats at run time to expose application vulnerabilities. Combined with the previous phase of SAST, DAST adds an additional layer of testing to eliminate most security errors.
Fuzziness testing: In fuzziness testing, developers generate random inputs that simulate custom patterns and check whether the application can handle them. This helps build protection against problems such as SQL injection, which is essentially malicious input.
Penetration testing: Inviting a team of third-party security professionals to simulate an attack is one of the best ways to expose hidden vulnerabilities in any system. It is always possible for development teams to overlook certain attack scenarios that the experience and knowledge of third-party experts might reproduce through penetration testing.
5. Deployment and maintenance
The developer’s work is not over when the application comes online. Applications have their own ecosystems that must be managed, maintained, and cared for.
Some SSDLC practices at this stage include:
Environment response: The application itself may be foolproof, but each application is only useful if it is relevant to the larger ecosystem. Once an application is started, monitoring the environment and its impact on the behavior and integrity of the application is a key aspect of maintenance.
Incident response planning: In the real world, no application is truly immune to security vulnerabilities. The incident response plan specifies the plans, actions, and procedures that the team must follow in the event of an incident.
Security checks: Threats and attacks are always evolving, and applications must evolve faster to remain secure. Frequent security checks help protect applications from new forms of attack and vulnerability.
In the traditional SLDC model, agile development has replaced the traditional approach to the development lifecycle in most organizations. However, agile environments are inconsistent with security-oriented practices and tools. This is mainly because agile development methods require extensive security testing. Because each phase is executed iteratively in Agile development, and security components are embedded in each phase of SSDLC, agile teams can find a lot of repeated testing.
This also means that integrating SSDLC into an agile environment requires a significant transformation for the enterprise. In agile development, security is no longer an afterthought, but needs to be incorporated into everyday work habits.
The ultimate goal of every enterprise is to embrace greater security by integrating at different stages and parts of development.
Reference link:
Resources.infosecinstitute.com/topic/intro…