Why your Active Directory needs a modern security strategy
7 minute read
Microsoft’s Active Directory (AD) manages user identities for roughly 90% of Fortune 1000 companies. It controls who can log in, what they can access, and which security policies apply to every connected device. That reach is exactly why attackers treat it as a high-value target, and why security teams should develop strategies that adapt to emerging threats.
Key takeaways
Active Directory is involved in 9 out of 10 cyberattacks, according to the Semperis 2024 Ransomware Risk Report. Its centrality to enterprise identity makes it the highest-value target in most organizations.
Traditional Active Directory hardening—static policies, periodic audits, perimeter firewalls—leaves gaps that attackers routinely exploit between review cycles.
A modern Active Directory security strategy layers adaptive authentication, single sign-on, device trust, and continuous verification on top of existing directory infrastructure.
Cloud directory services let organizations extend or replace on-premises directories without rebuilding their identity architecture from scratch.
New to directory services? Start with our guide to LDAP vs. Active Directory to understand the building blocks of your identity infrastructure.
Many Active Directory security solutions were designed for a world that no longer exists: one where every user, device, and application sits inside a corporate network. Hybrid work, cloud applications, and an expanding ecosystem of non-human identities challenge this security model and have forced teams to adapt.
Why is Active Directory such an attractive target for attackers?
Active Directory is the identity backbone of most enterprises. Compromising it can unlock access to everything the directory controls. The Semperis 2024 Ransomware Risk Report found that AD is the target in nine out of 10 cyberattacks, and that 83% of surveyed organizations were targeted by ransomware in the prior 12 months. IBM’s X-Force Threat Intelligence Index 2024 tells us why: 80% of enterprise cyberattacks use Active Directory to perform privilege escalation and lateral movement.
What do we mean by privilege escalation and lateral movement? These are pathways of attack that follow a familiar pattern.
An attacker gains initial access—often through a phishing email or a stolen credential from a previous breach—and lands inside the network with an ordinary user account.
From there, the goal is to move from that standard account to one with administrative rights. Attackers look for misconfigured permissions, unpatched domain controllers, or service accounts with excessive privileges that have not been rotated in months or years. This is privilege escalation.
Once they reach an administrative account, they move laterally, which means using one compromised system to access others. They pivot from machine to machine using the credentials and access the directory grants. At that point, the attacker effectively controls the organization’s identity infrastructure.
The Verizon 2024 Data Breach Investigations Report found that stolen credentials appeared in 31% of all breaches over the past decade, and accounted for 38% of analyzed breaches in the most recent reporting period. Directory infrastructure is where those credentials live.
Where do traditional Active Directory security approaches fall short?
We established above that the workforce has moved beyond the corporate network. What does that shift mean for the security controls most organizations still rely on.
Most Active Directory security best practices center on three mechanisms:
Perimeter firewalls between the internet and domain controllers
Static group policies applied uniformly to domain-joined devices
Periodic manual audits to catch misconfigurations
Each of these has a specific blind spot in today’s environment. Let’s break them down:
Perimeter firewalls protect domain controllers inside the network. They do not protect credentials traveling over a VPN, a cloud authentication service, or a remote desktop connection from an employee’s home network. When half the workforce authenticates from outside the perimeter, the perimeter is no longer the relevant security boundary.
Static group policies work well when every device is domain-joined and every user follows a predictable access pattern. In hybrid environments, employees use personal devices, contractors access internal applications through cloud portals, and service accounts authenticate around the clock. Here, a single set of static rules cannot account for the range of risk each session carries.
Periodic audits catch misconfigurations—eventually. A quarterly access review might surface an over-privileged service account, but an attacker who gains access between reviews has weeks or months to operate undetected.
Active Directory hardening protects the directory itself. But the users, devices, and applications it governs now operate in environments that hardening alone cannot reach.
What does a modern directory security strategy look like?
Modern Active Directory security solutions start with the assumption that no user, device, or session should be automatically trusted, regardless of where the request originates. This is known as zero trust. For AD, zero trust means replacing the old model of trusting the network and verifying at the gate with continuous, context-aware evaluation.
To do so, security teams layer several capabilities on top of existing directory infrastructure:
Single sign-on (SSO)
SSO lets users authenticate once and access multiple applications without re-entering credentials for each one. Integrating Active Directory SSO with a cloud identity platform reduces the number of passwords users manage and gives security teams a single point to enforce authentication policies, monitor access, and revoke sessions.
Device trust
Instead of trusting every device on the network, a modern strategy evaluates device health before granting access. Is the operating system patched? Is disk encryption enabled? Is the device managed by the organization? These checks happen at authentication time, not once a quarter.
Adaptive authentication
Rather than applying the same login requirements to every session, adaptive authentication adjusts based on risk signals. A user logging in from a recognized device on a familiar network might authenticate with a single factor. The same user from a new device in an unfamiliar location faces additional verification.
Continuous verification
Authentication does not end at login. Continuous verification evaluates trust throughout the session, checking for changes in device posture, network context, or behavior patterns that might indicate a compromised account.
How does moving directory services to the cloud help secure Active Directory?
A cloud directory service takes on the infrastructure burden that on-premises Active Directory requires: hardware, patching, replication, disaster recovery. But the benefit extends beyond operations.
Cloud identity platforms centralize authentication, SSO, user provisioning, and policy enforcement into a managed service. Organizations can extend identity management to users and applications that on-premises Active Directory was never designed to reach, including remote contractors, SaaS applications, and non-human identities like service accounts and API keys.
The transition does not require replacing Active Directory overnight. Most cloud identity platforms support directory sync, which means organizations can run existing Active Directory alongside a cloud directory and migrate users and policies at their own pace.
How do you start modernizing your directory security?
Modernizing directory security is a phased effort. Identity leaders who approach it as a strategic initiative, rather than a one-time infrastructure upgrade, tend to make more durable progress.
Take these steps to start this process:
Assess your current state. Map every system that authenticates against Active Directory. Include the ones easy to overlook: service accounts, legacy applications using LDAP, VPN appliances, and network devices. You cannot secure what you have not inventoried.
Identify the gaps that matter most. Where are credentials exposed? Which accounts have excessive privileges? How many service accounts have not had their passwords rotated in the past year? Prioritize based on exploitability.
Evaluate cloud identity options. Before choosing a modernization path, make sure your team understands the foundational differences between LDAP and Active Directory. Our guide to LDAP vs. Active Directory explains what each technology does, how they relate, and when to use each one. That foundation will help your team evaluate which cloud identity platform fits your environment.
Plan a phased migration. Start with the use cases where cloud identity delivers the clearest value: SSO for cloud applications, multi-factor authentication for remote access, automated provisioning for contractors and third-party users. Each phase reduces the attack surface while the core Active Directory infrastructure remains in place.
Ready to see how cloud-based identity can strengthen your directory security? Start a free Duo trial and explore Duo Directory