First step to controlling unauthorised access:

Assume they’re already in…

Because if you haven’t addressed the issue of access, it means team members almost certainly have access to things they shouldn’t.

Operating with a “worst-case” mindset shifts your focus from simply blocking threats to containing damage and constraining attackers before they spread.

Access risks come from both outside and inside your network. 

Phishing (or more widely social engineering), malware, and stolen credentials provide easy entry for external attackers. Meanwhile, excessive insider access can be just as dangerous, allowing attackers to leverage legitimate access to get sensitive data and exploit systems.

Effective access control is about stopping breaches from escalating and minimising their impact.

Organisations must ensure only the right people, with the right permissions, access internal systems. Anything less is an open invitation to potential security breaches.

So, here are 6 proactive ways to secure your internal systems from unauthorised access.

1. Use Role-Based Access Control (RBAC)

Role-Based Access Control (RBAC) is key to stopping unauthorised access. 

At its core is the principle of least privilege – a security standard that gives users the minimum access necessary to perform their tasks. This type of access control keeps sensitive data off-limits. 

With RBAC, access levels are set based on job roles and responsibilities.

For high-risk positions, like finance, customer data, or product design, RBAC can be your strongest protection against unauthorised access. For example:

A CFO could restrict payment system access to the finance team only, reducing the risk of fraud or data leaks.

Start by working with IT and security teams to set clear access rules for sensitive departments. 

Then run regular reviews to keep access up-to-date, as access tends to drift over time. Roles change, projects evolve, and temporary permissions often become permanent, leading to unnecessary risk. 

2. Implement Multi-Factor Authentication (MFA) and Get Familiar with Passkeys

Passwords alone aren’t enough…

Too many breaches occur due to weak or poorly managed security practices, and relying solely on passwords puts sensitive data at risk. Especially with the rapid rise of SAAS (Software as a service platforms) like Microsoft 365, Salesforce and the wave of much smaller web applications that people use each day to manage their core business functions like finance, (e.g Xero) and HR.

Multi-Factor Authentication (MFA) adds an extra layer of protection, making it far harder for unauthorised users to break in. It combines passwords with methods such as biometrics, one-time codes, or push notifications to truly verify identity.

Meanwhile, Passkeys are emerging as a modern and secure alternative to traditional passwords. Passkeys, which leverage device-based authentication tied to biometric or PIN verification, eliminate the vulnerabilities of passwords entirely. They are resistant to phishing, are easier to use, and provide a seamless yet highly secure login experience.

Use MFA and passkeys to safeguard all systems, with an immediate focus on your critical systems such as:

• Financial systems
• Online platforms and services
• Systems which hold PII (personally identifiable information)

Best Practices:

• Aim to roll out MFA and passkeys as a company-wide policy.
• Prioritise high-risk areas and remote access to maximise security where it matters most.
• Educate employees on the benefits of these technologies and provide resources for smooth adoption.

Extra compliance boost:

Both MFA and passkeys enhance compliance with data protection regulations such as UK DPA 2018/GDPR, particularly in high-risk sectors like finance and healthcare, by adding advanced layers of security. These measures demonstrate a proactive approach to safeguarding sensitive data.

3. Try User Monitoring and Behavioural Analytics

Behavioural analytics lets you catch threats before they become breaches. 

These tools analyse user activity in real time and flag unusual patterns, alerting security to potential unauthorised access or credential misuse.

Monitoring can spot the warning signs humans might miss, like: 

• Sudden access to sensitive files
• Logins from unusual locations
• Access during unexpected times
• Unexpected data transfers
• Impossible travel scenarios (where a user logs in from the UK then Australia within the space of a few hours.)

All clear signs of a possible compromise.

Early detection can contain breaches, avoid downtime, and protect against financial loss.

Work with your CISO to set up tailored alerts on high-value accounts and access points, keeping an eye on important internal systems. (If you don’t have a CISO you can always talk to us – we’re here to help).

4. Conduct Regular Audits and Access Reviews

Regular audits and access reviews keep access privileges up-to-date. 

This is especially necessary in dynamic work environments with high employee turnover, contractor usage, or role transitions. 

These reviews ensure only current employees have access to key systems, cutting risks from outdated permissions and stopping privilege creep.

The Head of IT should schedule quarterly reviews to verify access rights for all financial data and executive systems, ensuring only key staff have clearance.

As businesses grow and adapt, it’s easy for access privileges to expand unchecked, leading to potential risks. Regular audits reset the system and ensure access aligns with current responsibilities.

(Consistent audits also assist compliance with data security standards like ISO27001.)

5. Segment Your Network

Network segmentation is a powerful way to contain the impact of any breach. 

It puts layers of protection around your most critical assets (you know what these are, right?). 

By isolating sensitive data and key internal systems, segmentation ensures that even if hackers gain access to one area, they can’t easily move across your network.

Focus on segmenting important, high risk systems, like financial databases, intellectual property storage, and HR systems from less sensitive areas. 

Even if a lower-priority system is breached, high-value areas remain secure and out of reach.

6. Invest In Identity and Access Management (IAM)

Identity and Access Management (IAM) puts you in full control over who can access what within your organisation.

With IAM, you can automate:

• Onboarding / offboarding
• Role-based adjustments
• Monitoring and reporting

In practical terms, IAM can automatically revoke access when contracts end or roles change, closing security gaps instantly.

IAM also simplifies audits, making compliance straightforward, with all documentation readily available. 

Top Tip: Look for IAM solutions that offer scalability and automation to streamline your access management process.

7. Simplify Access with Single Sign-On (SSO)

Single Sign-On (SSO) allows users to access multiple systems with just one set of login credentials, streamlining access and improving security. By reducing the number of passwords employees need to remember, SSO minimises the risk of weak or reused passwords – a common entry point for attackers.

Whilst SSO falls more into the authentication arena we felt important to mention it, as it’s a critical part of ensuring your overall access management strategy. 

SSO centralises authentication, giving your IT team better visibility and control over access across all your systems. It also reduces the likelihood of password fatigue and phishing attacks, as users only interact with one trusted authentication point.

Best Practices:

• Pair SSO with Multi-Factor Authentication (MFA) for an extra layer of protection.
• Use SSO for critical systems and applications, prioritising platforms with sensitive data or high user traffic.
• Ensure your SSO provider complies with recognised security standards, like SAML (Security Assertion Markup Language) or OpenID Connect.

Benefits Beyond Security: SSO boosts productivity by cutting down login times and reducing IT support tickets related to password resets. For larger organisations, this can mean significant cost savings and fewer disruptions.

Top Tip: Choose an SSO solution that integrates seamlessly with your existing IAM and MFA setup, creating a robust and user-friendly security ecosystem.

Protect Your Internal Systems with Control Access

Strong access controls are a must. 

They protect your business from greater financial loss, reputational damage, and operational disruptions in the event of a breach. 

But access control goes beyond securing your internal systems. They build a security-first culture that strengthens every part of your organisation. 

With leadership driving these strategies, sensitive data stays locked down, accountability rises, and overall security gets a much needed boost. 

Ready to secure your internal systems? Cyber Alchemy can tailor security solutions to your needs.

We offer thorough assessments to identify potential vulnerabilities in existing access controls and expert guidance on implementing industry best practices. 

Contact us today and start protecting what matters.