When it comes to information security and the management of system access and identities, much of the conversation tends to revolve around tools and rules designed to strengthen governance. But is relying solely on technical controls really enough in the face of increasingly sophisticated threats?
In my research on the subject, I came across an analysis published in September 2024 by Asad Abbas, which highlights the importance of the Principle of Least Privilege and Segregation of Duties as fundamental mechanisms for reinforcing cyber defense. Inspired by his perspective, I want to explore how these concepts, applied to the context of access and identity, emerge as crucial foundations for mitigating information security risks.
The reality, however, is that these principles are often overlooked or prove difficult to implement within organizations. Yet, when applied, they can serve as powerful safeguards against crises that might otherwise compromise sensitive data, disrupt operations and compromise trust.
Least Privilege and Segregation: The Invisible Foundation of Defense
The Zero Trust approach to access management, at its core, is built on the idea of “never trust, always verify” breaking away from the assumption that corporate users and devices are automatically trustworthy. This mindset reinforces three fundamental pillars: the principle of least privilege, the presumption of breach and the need for continuous protection. Together, they foster a culture where trust must be earned at every interaction or request.
Segregation of Duties (SoD) strengthens this philosophy by emphasizing the division of critical responsibilities, ensuring that no single access credential (or user) controls key steps in a process. In other words, it’s not just about authentication and access validation mechanisms, it’s about structuring the identity environment so that no user accumulates more power than they truly need, and each credential is used strictly within its intended purpose.
The relevance of these principles is far from theoretical. In 2025, for instance, the system used by Brazil’s Central Bank and National Justice Council exposed data from more than 11 million people, demonstrating how failures in access management can put sensitive information at risk. That same year, the U.S. Department of Government Efficiency (DOGE) also faced incidents due to vulnerabilities in its internal systems, allowing unauthorized access to critical information. These episodes, in very different contexts, make it clear that when rigorous controls, such as least privilege and segregation of duties, are absent, isolated failures can escalate into massive crises.
The Starting Point of True Security
When we understand that identity security begins with the combined application of segregation of duties and the principle of least privilege, all other control practices naturally emerge as consequences of these foundations. For example, the use of multi-factor authentication (MFA) reinforces the idea that no access should ever be assumed, requiring continuous validation. Privileged Access Management (PAM), in turn, ensures that critical credentials are controlled and used only when strictly necessary.
There is also the identity lifecycle, which seeks to guarantee that accounts are properly provisioned and deactivated, preventing inactive or excessive access. Together, these and other stop being merely additional controls and instead become extensions of privilege limitation, stemming from the distribution of responsibilities.
Even so, I endorse the view that the truly indispensable paths to strengthening organizational information protection demand, above all, a shift in mindset: structured prevention, based on zero trust and the division of responsibilities, leaving no room for loopholes or excessive privileges.
Focusing on the Foundation Makes All the Difference
In today’s ever-evolving digital world, true identity and access security management does not begin with advanced tools or isolated policies, but with strengthening the fundamentals that sustain it. As Abbas rightly emphasized, when these pillars are placed at the center of the strategy, it becomes easier to correlate and implement complementary management practices. This integration, aligned with business needs, not only strengthens governance but also enables the construction of a solid foundation to face increasingly sophisticated threats.
That is why I invite you to approach identity and access management from the perspective of effective and systematic integration between the principles of segregation of duties and least privilege. In practice, this is the true premise of a philosophy of controlled access, distributed and limited to what is necessary, and the essential foundation for turning strategies into organizational resilience.
