Security is a crucial aspect of software design, but it can also be challenging and complex. How do you approach it from the start, without compromising functionality, usability, or performance? In this article, we will explore some key steps and principles to help you design software that is secure.
The first step is to identify the potential threats and risks that your software may face, and how they could affect your users, data, and resources. You can use various methods and tools to perform a threat analysis, such as STRIDE, DREAD, or OWASP Top 10. These will help you to classify the threats according to their source, type, impact, and likelihood, and prioritize them accordingly.
To design secure software, I start by conducting a thorough risk assessment to identify potential vulnerabilities and threats. This involves analyzing the application's architecture, data flow, and dependencies. Next, I implement security best practices such as input validation, parameterized queries, and encryption techniques to mitigate known risks. Additionally, I prioritize security features such as access control, authentication, and logging mechanisms to detect and prevent unauthorized access or malicious activities. Regular security audits and testing, including penetration testing, are crucial to ensure ongoing protection against evolving threats.
Designing secure software is hard. Often times the hardest part is to introduce security at a later stage which is often, because introducing security earlier on is viewed as a slow-down by most teams. This leads to insecure and hard to secure products. There are lots of good techniques of designing secure software like Zero-Trust, principle of least privilege etc, but one way that I have used in the past is to create a Threat model and be truthful about all attack vectors and list them down. Every secure system has some flaws, know them and isolate them. Moreover, security is a continuous investment. You have to constantly re-evaluate your thread model and the known vectors. Validating assumptions is also important - pen tests etc help!
Well I would start with the requirements first. Why does this software have to be secure. What has to be achieved. Who is using the software and how is it used. Only then I would start with the threats. Without with this understanding it will be hard to see those in context.
When tasked with designing secure software, I'd adopt a comprehensive approach. First, I would delve into understanding the software's purpose, intended users, and usage scenarios. This initial phase would allow me to contextualize security needs. Following this, a methodical threat modeling process would be initiated. By mapping out the software's architecture, identifying potential vulnerabilities, and categorizing assets, I'd lay the groundwork for a robust security framework. Prioritizing security measures based on recognized threats and potential consequences ensures a targeted and effective approach to building a secure solution.
Try to classify the design into user space, system space, and kernel space during the development of software design. Identify the key areas (vulnerable) in the design w.r.t to spaces, and divide key areas into two levels. The first level is to identify potential vulnerability within the space (US, KS, SS), and the second level is among the space (interaction b/w different spaces) This process will make a threat model matrix and then start deriving potential surface attacks for each case. Mark all those elements of the matrix that look to be a tentative attack in context with design, this evolve side channel attack test cases. Start coding, follow secure coding, perform threat analysis, and on completion execute your threat modeling matrix.
The next step is to apply some general principles of secure software design, such as defense in depth, least privilege, fail-safe defaults, economy of mechanism, complete mediation, open design, separation of privilege, and psychological acceptability. These principles will guide you to design software that is robust, resilient, and reliable, and that minimizes the attack surface, the damage potential, and the user burden.
Secure software systems need to be designed using the principles used in industry and also make a separate unique secure design element that will be helpful against intruders. That specific element may be a encrypted key or something else other than the access token, etc.
The "secure" for me is actually just a term. There are no such applications that can say they design "securely". They could due to many reasons like libraries, os , language so on. People in the community will still finds exploit or vulnerabilities. The way that can keep your applications safe is make sure to patch all the updates and make sure all bugs resolve immediately.
The third step is to choose the appropriate technologies and frameworks that support your security goals and requirements. You should consider factors such as compatibility, scalability, maintainability, and performance, as well as the security features and vulnerabilities of each technology. You should also follow the best practices and standards for secure coding, such as OWASP Secure Coding Practices, and use tools such as code analyzers, linters, and scanners to detect and fix any issues.
In the context of designing and implementing a solution for GDPR compliance requirements, I had an opportunity to evaluate and choose an Enterprise Key management solution (KMS). Such technologies at Enterprise scale can easily cost upwards of $ million, and so it is imperative to clearly lay out the problem domains to be addressed, such as Secrets management, Data encryption and decryption, Key management and Certificate management. Accordingly shortlist Tech vendors based on coverage of their offerings to your problem domain, followed by a deep dive into their architecture, capabilities, efforts required analysis into rollout/deployment and adoption across the Enterprise applications landscape and cost/licensing and support models.
The fourth step is to implement the necessary security controls and mechanisms that protect your software from the identified threats and risks. These may include authentication, authorization, encryption, hashing, digital signatures, certificates, firewalls, anti-virus, logging, auditing, backup, recovery, and more. You should also test and verify the effectiveness and functionality of your security controls, using methods such as unit testing, integration testing, penetration testing, and code review.
Authorization and authentication are the initial steps in developing a secure software platform. Use credentials to identify individuals if you want only certain users to have access to the application. For instance, you have an employee directory application that uses email addresses to categorize different employees. In such a scenario, before storing the emails in the database, you must encrypt them.
The fifth step is to educate the users and stakeholders about the security aspects of your software, and how they can contribute to its safety and integrity. You should provide clear and concise documentation, training, and guidance on how to use your software securely, and how to avoid common pitfalls and mistakes. You should also communicate the benefits and value of your security design, and solicit feedback and suggestions for improvement.
The final step is to update and monitor your software regularly, and respond to any new or emerging threats and challenges. You should keep track of the latest security trends, developments, and incidents, and apply patches, fixes, and enhancements as needed. You should also monitor the performance, behavior, and usage of your software, and detect and report any anomalies, breaches, or incidents. You should also review and evaluate your security design periodically, and make adjustments as necessary.
Updating your code regularly to keep up with emerging threats is key. Code that is secure and functional now will be a sitting duck in a couple of years. Operational threat modeling on a regular basis will also help identify what to update. This will also identify gaps between Threat Modeling done at the Design phase and post-implementation phase.
It's easy to think it's just software that must be secure. I'd start back with making sure the organization understands the nature and importance of security so that it's prepared to adapt as needed in terms of processes, planning, infrastructure, budget, and even culture. Clean, protected transport and storage of data, sure, but also a culture that rewards people calling out their own errors or worries without fear of rebuke. Some goals are in tension with one another, so trade-offs must be made. Centralization and efficiency, common goals, can invite security risks. Open source has benefits, but challenges, too. Software should avoid problems, but processes must be in place for when that fails. It's a whole-organization effort.
Security isn’t really a design problem; it’s a utility service to the rest of the system. It shouldn’t impact the design; instead, it should be an available service to all the system components.
First, identify potential threats. Second, understand that you can’t identify all possible threats and design the system accordingly. In particular (but not only), use out of the box trusted solutions, and also don’t trust anything that arrives to your server from a client. Good luck!
To create secure software, you should start by identifying potential risks and vulnerabilities. Think about how users might misuse the software or how external attackers could exploit weaknesses. Then, set up strong authentication measures to ensure only authorized users can access the system. Regularly update your software and its dependencies to patch any known security issues. Encrypt sensitive data to protect it from unauthorized access, and use secure coding practices to prevent common vulnerabilities. Conduct thorough testing, including security testing, to identify and fix potential problems before releasing the software.
Security measures are essential to safeguard sensitive data, protect against cyber threats, and maintain user trust. However, these security measures can sometimes introduce complexities that hinder usability. As a software designer, we need to find the sweet spot.