Enterprises are discovering something important, and they’re discovering it quietly.
For years, security programs invested heavily in perimeter controls, network defenses, and endpoint hardening. And those investments mattered. They still do.

But as attacks have evolved, one truth has emerged with a kind of gentle clarity:
identity has quietly become the real perimeter.

And inside most organizations, there is one identity system that shapes everything else, the place where authentication, trust, and privilege converge.

Active Directory.

Not new. Not flashy. Not cloud-native. But foundational in a way that becomes unmistakable the moment something goes wrong.

The Pattern Behind Today’s Most Disruptive Breaches

Ransomware events. Supply chain intrusions. Business email compromise. Privileged access takeover. Despite differing entry points, these attacks consistently converge on the same destination: Active Directory.

Why?
Because AD governs:

• Who can access which system?
• How trust is established.
• How privileges escalate.
• How applications authenticate.
• How infrastructure interacts.

Compromise AD, and you compromise the business.

This is why identity has become the new perimeter, and why AD security is no longer a technical task, but a strategic resilience priority.

Enterprise Identity: The Path of Least Resistance for Attackers

Modern attackers don’t want noisy exploits or brute-force techniques. They want credentials, privileges, and access pathways that let them move quietly.

Identity gives them exactly that.

Active Directory remains deeply embedded in most enterprises, often carrying years of:

• Permission sprawl.
• Legacy configurations.
• Outdated protocols.
• High-privilege accounts.
• Unmonitored service accounts.

This makes AD the perfect place for attackers to hide, escalate, and persist. They pivot into privileged pathways that have existed quietly for years.

But what’s equally true is that organizations have more control over these pathways than they realize.
Modern AD hardening is not about chasing new tools. It is about addressing long-standing patterns that, once corrected, reshape an enterprise’s resilience almost immediately.

What Strong AD Hardening Actually Looks Like

It doesn’t begin with sweeping architectural changes. It begins with foundational practices that reduce risk in ways that are meaningful and measurable.

Reduce Privilege to Reduce Blast Radius

Privilege is the currency of cyberattacks. The fewer privileged accounts that exist, the fewer opportunities attackers have to take control.

Enterprises must:

• Minimize admin groups.
• Continually review privileged memberships.
• Eliminate “temporary” elevated access that becomes permanent.
• Ensure privileges match actual business needs.

Excess privilege isn’t just a misconfiguration; it’s a strategic liability.

Standardize Access Through Groups, Not Individuals

Managing permissions one user at a time creates inconsistency.
Assigning permissions through structured groups creates:

• Governance
• Auditability
• Predictability
• Reduced human error

Organizations that standardize permissions through groups make identity more consistent, more governable, and significantly harder to exploit.

Protect Administrative Accounts Like the Crown Jewels They Are

Administrator accounts are the first target for lateral movement.

Enterprises should:

• Prevent admin accounts from logging into non-admin systems.
• Restrict their use to hardened workstations.
• Mark them as sensitive and non-delegable.
• Monitor them continuously.

Admin accounts should live in a world of their own: controlled, monitored, and insulated from everyday systems. This alone changes the trajectory of most attack paths.

Modernize Password Security for Today’s Attack Techniques

Traditional complexity rules no longer defend against modern attacks.
Today’s threat actors rely heavily on password spraying and offline cracking, not brute force.

Modern password strategy means:

• Banning common passwords.
• Encouraging long passphrases.
• Avoiding unnecessary password rotation.
• Enforcing stricter policies for privileged accounts.
• Using fine-grained password policies for sensitive groups.

Security improves when passwords become harder to guess, not harder to remember.

Secure Service Accounts: The Most Exploitable Identities in AD

Service accounts often have powerful privileges and weak governance.
Attackers exploit them using techniques such as Kerberoasting, often gaining domain-level access within minutes.

Best practices include:

• Very long, vault-managed passwords.
• Automatic password rotation.
• Reviewing where service accounts are used.
• Avoiding shared credentials.

These accounts must be treated with the same seriousness as administrator identities.

Eliminate Legacy Protocols That Introduce Modern Risk

Some long-standing Windows components now pose outsized risk, particularly on critical systems such as domain controllers.

Organizations should:

• Disable the Print Spooler on domain controllers.
• Decommission SMBv1.
• Reduce reliance on NTLM where possible.

These changes remove entire categories of attack.

Lock Down Domain Controllers as Tier-0 Assets

Domain controllers should be accessible only to the most trusted personnel and systems.

That means:

• No browsing from DCs.
• Strict remote access rules.
• Hardened administrative channels.
• Segmentation from lower-tier systems.

A domain controller is not a server. It is the identity authority of the enterprise and must be treated as such.

Plan for Recovery Before an Attack Happens

Identity recovery is business recovery. Organizations must ensure:

• Multiple offline AD backups.
• Prepared domain and forest recovery procedures.
• Clear delineation of roles during recovery.
• Tested restoration workflows.

A ransomware attack is not the time to learn how AD recovery works.

Monitor for the Subtle Changes That Signal Compromise

Some AD objects change rarely in legitimate scenarios, so monitoring them is invaluable. Unexpected modifications to privileged groups, delegated permissions, sensitive security objects, or configuration policies should be treated as high-risk events.

Identity compromise starts quietly. Monitoring makes it loud.

AD Hardening Is Now a Board-Level Conversation

Boards increasingly ask CISOs questions like:

• “How exposed are we to identity compromise?”
• “Do we have excessive privilege in AD?”
• “Can we recover our identity systems after an attack?”

These are not technical questions; they are business continuity questions. Active Directory sits at the center of all of those questions.
Not loudly. Not prominently. But undeniably.

A Quiet but Essential Shift

Active Directory is still the backbone of enterprise authentication. If it is not secure, nothing built on top of it can ever be secure.

NuSummit helps organizations build AD hardening programs that:

• Protect identity at its core
• Reduce operational risk
• Strengthen cyber resilience
• Support board-level governance requirements

Identity is the new perimeter, and AD is the first place to reinforce it.