Legacy Systems, Lost Knowledge: How Employee Turnover Threatens Cyber Resilience

Employee turnover is a multi-layered and expensive problem, from the cost of hiring a replacement to the time required for employee offboarding. When employees leave, they don't just take their knowledge and experience; they can also create significant security risks. The period following an employee's departure opens a dangerous window for insider threats and unauthorized access, especially for companies that use outdated, manual user lifecycle management processes. To protect against these cybersecurity risks, a secure and automated employee offboarding process is essential.

Even under the best of circumstances, the period following an employee's departure opens up a dangerous window for insider threats, whether intentional or accidental. This is especially true for companies that rely on outdated, manual processes for managing employee accounts and access. 

Is your organization among them? If so, you’re definitely not alone. In fact, a recent study found that 89% of employees retain access to sensitive systems and accounts long after their departure. 

Yikes. When cyberattacks are on the rise and the cost of a data breach is at an all-time high, can you afford to leave yourself vulnerable to these threats? 

How Long Does It Take Your Organization to Revoke Access? 

The most significant identity security risk related to turnover  comes when you  fail to properly and immediately revoke access for departing employees. Whether they are fired, laid off, changing jobs, or retiring after 30 fulfilling years, the period following an employee departure is a  dangerous window of opportunity for insider threats, whether intentional or accidental.

• Access Revocation: How long does it take your organization to revoke access? I f an employee's accounts and access rights aren't disabled  immediately  upon their departure, they may still be able to log in to corporate systems, email, and applications. This "ghost access" can be exploited by a disgruntled former employee , who could steal and leak sensitive data or even sabotage your systems. In this scenario, the math is clear. Lag time = risk.
• Data Exfiltration: All employees, but  especially those with a  negative or fraught  relationship with the company, may copy confidential data to a personal device or account  if they retain access after their departure. This could include customer lists, intellectual property, or trade secrets, which poses a serious threat to the company's competitive advantage and reputation.
• Social Engineering: Most organizations have hidden, inactive accounts lurking in the shadows, unnoticed. These invisible  accounts are  prime targets for cybercriminals, who could take over the account and use it to launch phishing attacks against other employees or partners, manipulating them into revealing sensitive information.

What About the Risks from Incoming Employees? 

So glad you asked! Often when we talk about turnover risks we focus on the employees who are leaving, but that’s just one side of the coin. On the other side, turnover also introduces risks by way of new hires, who may not know how to protect themselves from cyber threats, never mind how to protect your organization.  

For example, new employees may not be aware of common cyber threats like phishing, social engineering, and weak password hygiene. This lack of knowledge makes them an easy target for external attacks, since they are more likely to make a mistake that could compromise the company's network.

In workplaces with high turnover, IT and HR departments often struggle to keep up with user provisioning and assigning appropriate access rights. Manual processing of Joiner, Mover, Leaver (JML) procedures leaves your organization vulnerable to errors that could grant a new employee excessive privileges, directly impacting identity and access management (IAM). This highlights the need for an automated onboarding solution.

Another way that turnover exposes your organization to risk is the inherent risk of hiring a new person who isn’t already known to you. In recent years, several companies have fallen prey to imposters posing as legitimate job seekers. In these scams, North Korean hackers, among others, are pretending to be someone they are not in order to land the job and get credentials to freely access your networks. 

Building a Secure Offboarding Process

Onboarding and offboarding are most efficient when you have clear, well-articulated processes rooted in strong identity security principles like Zero Trust and the Principle of Least Privilege.  A secure onboarding process ensures that right person is given the right access at the right time, while an efficient offboarding process ensures that access is revoked completely and immediately, when an employee departs.

Secure Employee Onboarding Step-by-Step

The goal of a secure onboarding process is to verify an individual's identity unequivocally and grant them the minimum necessary access to perform their job. This is the foundation of effective access management and preventing privileged access abuse.

Guiding Principles for Secure Onboarding

• Verify User Identity: Confirm the user is who they claim to be before granting any access.
• Principle of Least Privilege (PoLP): Grant access only to the systems and data explicitly required for their role.
• Role-Based Access Control (RBAC): Group permissions into roles to make provisioning consistent, auditable, and scalable.
• Day-One Productivity: Balance security with enabling the new hire to be productive as quickly as possible.

Phase 1: Pre-Start Date 

This foundational phase is all about preparation and occurs entirely before the new hire's first day. It involves verifying the employee's background and creating their core digital identity and application accounts in a disabled, non-accessible state. By pre-provisioning access based on their defined role and preparing their hardware, IT and HR set the stage for a secure and efficient Day One activation without granting any live access prematurely.

Phase 2: Day One  

Day One is the critical activation point where security theory becomes practice. The process begins with a final, in-person or video-based verification of the employee against their government-issued ID. Only then is their account enabled, allowing them to set their password and, most importantly, enroll in Multi-Factor Authentication (MFA) as a mandatory step. This phase ensures that access is only granted after the individual's identity is unequivocally confirmed and they have secured their new account.

Phase 3: First 30 Days 

The first month focuses on refining the new hire’s permissions and reinforcing security culture. The employee completes mandatory security awareness training while their manager formally reviews their initial access rights to ensure they align with the Principle of Least Privilege. This phase is about transitioning from broad, role-based access to a fine-tuned set of permissions, ensuring the employee has only the access they need to be productive, and nothing more. 

Efficient Employee Offboarding Step-by-Step

The goal of an efficient offboarding process is to mitigate the security risks posed by departing employees with timely access revocation.

Guiding Principles for Efficient Offboarding

• Speed: The moment an employee's departure is confirmed the process must begin.
• Completeness: Automation is key to ensuring that no account, asset, or access point can be missed.
• Knowledge Transfer: Take steps to ensure that valuable company knowledge doesn't walk out the door.
• Positive Last Impression: Treat the departing employee with respect.

Phase 1: Immediately Upon Notification of Departure 

This phase begins the instant an employee's departure is confirmed. Its goal is to immediately trigger a coordinated, automated offboarding workflow that notifies all stakeholders (IT, HR, Management). Key actions include creating a formal knowledge transfer plan and assessing whether any high-risk privileged access needs to be revoked ahead of the employee's final day to mitigate immediate threats.

Phase 2: The Notice Period 

The notice period is dedicated to a smooth and complete transition of responsibilities and digital assets. Guided by their manager, the departing employee executes the knowledge transfer plan, ensuring that all project files and critical information are moved to shared, centrally managed locations. This proactive phase prevents operational disruption and ensures valuable company intelligence is retained after the employee leaves.

Phase 3: The Last Day 

The employee's last day is a time-sensitive execution phase focused on complete separation. It involves a final exit interview, the physical recovery of all company assets (laptop, badge, etc.), and—most critically—the automated disabling of their primary account at the end of the workday. This single action revokes access to all integrated systems, ensuring a clean, immediate, and secure exit.

Phase 4: Post-Departure 

The work isn't finished when the employee walks out the door. This final phase involves administrative cleanup and data lifecycle management. The employee's email is temporarily converted to a shared mailbox for business continuity, their data is archived according to retention policies, and after a designated cooling-off period, their account is permanently deleted. This ensures no orphaned accounts remain as potential security risks while complying with data management regulations.

Are You Ready for Secure Onboarding and Offboarding? 

KeyData Cyber can help! With a deep bench of over 200 IAM specialists with deep expertise in advisory, implementation and managed services, we help organizations just like yours close their critical security gaps. Contact us to schedule a complimentary IAM assessment and receive a roadmap to a more secure future.