How to Integrate Security Across Various SDLC Phases for Effective Protection


When organizations create apps, they focus on creating robust applications with a gamut of benefits to offer their customers. Unfortunately, sometimes they pay little attention to the security of the application which can lead to delayed identification of defects mostly at the verification phase.

It is far more cost-effective to identify and fix defects early in the development process than to patch them during a later stage.

Therefore, security shouldn’t just be a part of one stage in the software development life cycle (SDLC). It should be a top priority and integrated throughout the SDLC to ensure effective protection.

While it is essential to create a solid product, it is just as important to safeguard it against threats and attackers. Doing so can help you reduce vulnerability, manage expenses, build credibility, and garner the trust of your clients.

Here are some phase-specific ways to infuse security into each and every stage of the SDLC:

Phase 0: Foundation

The first step to integrating security into all stages of the SDLC is to build a security-aware workforce. It is essential for organizations to acknowledge the importance of a strong security culture and educate its workforce to adopt better security practices.

General training and awareness programs about security methodologies, policies, procedures, best practices, and assurance should be regularly organized to promote an enhanced security culture throughout your organization. This can help you establish a positive security culture in which all teams are involved in maintaining the security of the organization.

Moreover, specialized training programs for project managers, developers, and QA teams should also be conducted to empower them with knowledge of the latest security challenges and how to overcome them. Establishing a comprehensive risk management process will also come in handy when a threat or potential vulnerability crops up.

A security-aware company culture has far-reaching benefits that can change the way the management team makes decisions. An efficient risk management process can help facilitate the early detection of potential weaknesses and problems that could be addressed before they turn into a threat and impact the SDLC.

Phase 1: Requirements Gathering

Gathering the correct requirements is a critical part that determines the entire course of the journey for effectively integrating security into your SDLC. By generating security requirements, you will be able to create a solid security mindset from the initial phase of the SDLC.

During this stage, analysts need to determine potential application vulnerabilities and detect threats that could pose problems in the SDLC.

To do so, ask questions that focus on security requirements such as:

  • Do you handle sensitive data? (personal information of customers such as user credentials, credit card details, banking account details, social security numbers, health insurance information, etc.)
  • How many employees have access to sensitive information?
  • Is your network secured end-to-end via encryption?
  • Do you upload/download files regularly?
  • Is your cloud computing system secure?
  • Are your software applications up-to-date?

By identifying risky areas that could leave room for a potential vulnerability, you can address those issues and reduce the chances of security breaches in your organization. Developing base security stories to tackle future security-related issues is also an effective way to strengthen the overall security of the SDLC.

Consider implementing an industry-standard security model such as the Consortium for IT Software Quality (CISQ) which developed standards tor automate the evaluation of software structural quality and size.

These standards are based on the exploits determined by the Open Web Application Security Project (OWASP), SANS Institute, and Common Weakness Enumeration (CEW), which are most commonly used to manage risks such as application security.

Phase 2: Design and Architecture

Most software defects that create security issues are introduced during the design and architecture phase. Teams should continue performing risk analysis to identify possible loopholes in the software that could lead to threats and impact the SDLC during a later stage.

There are several ways you can identify potential bugs early in the SDLC, including:

Threat Modeling

Threat modeling allows teams to keep the existing and new threat models together. This way, if there are changes to the threat landscape or the IT environment, they can be monitored in real-time to identify new attacks that might have surfaced after the recent changes.

Moreover, continuous threat modeling will help you measure and quantify the effectiveness of your security initiatives.

Security Control Design Analysis (SCDA)

SCDA determines whether or not security controls align with industry best practices. For example, it may detect a password that is stored in plain-text such as PASSWORD instead of a salted hashed format such as NASDLFNS3658NDA9.

Architecture Risk Analysis

This type of analysis adds known attack analysis and dependency analysis to threat modeling, seeking for flaws which could allow security breaches or attacks. It prioritizes technical risks as per their severity which helps teams address severe threats or issues quickly.

Phase 3: Implementation

During the implementation stage, the application is completed by the developers as per the established specifications. Security activities during this stage include automated code reviews, static application security testing, as well as technology-specific secure coding guidelines.

Secure Code Review

A secure code review verifies the source code of an application to determine whether it has proper security controls present and if they are working as intended. This can help identify vulnerabilities in the application.

It detects inconsistencies that were not detected in the previous stages and ensures that the business, as well as the logic code, is sound.

A secure code review is an efficient way to detect flaws in authentication, data validation, encryption, session management, authorization, logging, or error handling.

Static Application Security Testing (SAST)

Static application security testing, (also known as “white-box testing”), is one of the best ways to ensure application security.

SAST tools, (such as a source code analysis), determine high-risk software vulnerabilities like Structured Query Language (SQL) injection, which would impact the system throughout the SDLC.

These tools can easily integrate with an already established process of the SDLC and work efficiently with bug trackers, and other testing tools.

Technology-Specific Secure Coding Guidelines

Technology-specific security guidelines are typically created in the form of checklists that help developers code securely.

These checklists often include things to avoid with secure alternatives. These guidelines should be language or framework-specific (e.g., Java) and should be actionable (e.g., how can developers implement this securely?)

Phase 4: Verification

During the verification stage of the SDLC, developers and/or testers assess their applications for defects. For instance, if a user enters an amount smaller than 1, the transfer button of the banking app should not function.

Security activities in the verification stage look for security defects in the application while it runs.

Here are a few examples of potential security defects:

  • The webpage is vulnerable to cross-site scripting
  • The application stores the password in plaintext instead of hashed salted form
  • A mobile banking app allows transfers of negative amounts (i.e., money is transferred from someone else’s account into yours)

Some of the most popular and effective testing methods to identify defects in an application during the SDLC include:

Penetration Testing

A penetration testing assessment explores vulnerabilities in your application or system configurations and network infrastructure. While small vulnerabilities may appear negligible, they can pave the way for cybercriminals to create intrusions and carry out attacks. A penetration test can help find such vulnerabilities.

For example, a banking application should ideally lock out the user after multiple failed attempts to log in. But if that’s not the case, an attacker may attempt to brute-force passwords.

Such defects are easily identified by conducting a penetration test. The tester can also use dynamic application security testing (DAST) tools to automate these tests.

However, one of the major drawbacks of using DAST tools is that they can produce false positives. This means that testers need to verify each of the discovered findings.

Interactive Application Security Testing (IAST)

IAST helps organizations identify security risks associated with vulnerabilities discovered during the runtime of the application using dynamic testing tools. It tests only whatever is exercised by the functional test.

IAST combines DAST tools with a runtime component to significantly reduce false positives. The runtime component is embedded into the runtime of the application which enables it to gain insights into the code path that the application has taken under the attack conducted by the DAST tool. This helps the IAST tool decline attacks that are most likely to be false positives.

Fuzz Testing

During fuzz testing, either semi-automated or automated techniques are used to detect errors in coding as well as weaknesses in the security of the application. In this form of testing, the tester intentionally sends malformed input to the application.

For example, a tester could input an invalid password for a user’s account to verify whether it accepts it or not. Fuzz testing is highly efficient when combined with black-box testing and other debugging methods.

Since verification is done at the end of each sprint in Agile environments, developers can easily use this security testing method to quickly assess the application for defects.

Phase 5: Deployment and Maintenance

Hardened configuration of services, servers, and deployment processes should be enforced to strengthen the overall security of the SDLC.

Security activities that take place under this phase include:

  • Keeping the operating systems of your servers up-to-date
  • Enforcing strong password policies
  • Using encryption keys wherever possible
  • Updating or removing third-party software
  • Leveraging the power of anti-virus and firewalls
  • Install the appropriate post-Service Pack security hotfixes
  • Using least privilege access

All of these activities are conducted to ensure that the best security practices are being followed to reduce risks and threats in the future.

Once the application is deployed, testers should conduct a red team assessment. During this activity, testers analyze the application under a modeled real-world adversary and assess how it would hold up against the attack.

They also evaluate the application’s security when multiple vulnerabilities, (which may seem small on their own), attack the system together.

Similar to real-world attackers, testers consider not just weaknesses in the application but also weaknesses present in the environment in which the application is deployed (e.g., firewalls, networks, and operating systems) and mimic a real-world attack.

While you may have conducted multiple tests to identify and mitigate potential bugs, there is a chance that your application might have security flaws after deployment.

Security practices need to be followed throughout software maintenance. Apps need to be continuously updated with the latest security measures to ensure that they are safe from attackers.

To do so, create a flexible yet powerful plan for software maintenance and a change management process that will be able to efficiently handle bugs that come out of production.

It is also important to have disaster recovery requirements and rollback plans available to help ensure customer confidence.


The security threat landscape is evolving rapidly. It’s only a matter of time before a vulnerability impacts your business. However, by taking corrective security measures, you can integrate security throughout the SDLC.

An incident response group prepared to execute a suitable immediate plan is essential to ensure the security of the enterprise and the deployed product. The group should be well-equipped and experienced to quickly respond to unexpected incidents to minimize or contain the damage.

By implementing the practices above, you can embed security as a major part of your SDLC and mitigate risks early in the process.