When was the last time you could say exactly who and what can authenticate in your Active Directory (AD)?
For most organizations, the honest answer is ‘not recently’. AD still runs authentication and access for the majority of enterprises. However, after decades of group sprawl, mergers and acquisitions, and configurations no one has ever revised, most AD environments carry years of identity tech debt: legacy protocols, over-permissioned accounts, shadow admins, and credentials set so long ago no one wants to touch them now.
But here’s an uncomfortable truth: compromising AD rarely takes a complex exploit. Most attackers are not looking to find something new. It’s about abusing the same protocols and privileges that keep business running.
They harvest a Kerberos ticket, relay an NTLM authentication, compromise an overprivileged service account, and move laterally from host to host until they reach domain-level control. Every step looks legitimate, because it happens inside AD’s own trust model. And in the era of AI-powered attacks, that whole sequence runs faster than any team can respond. Some research even reports that attackers can compromise AD in just about 2 hours.
That’s what AD hygiene is really about: finding and fixing those weaknesses, and shrinking the attack surface, before someone else finds them for you. In this blog, we’ll walk through five of the highest-impact places to start, and how Silverfort helps you close critical security gaps.
Maintaining proper AD hygiene is essential
AD hygiene is the set of practices that keeps your AD environment clean, organized, and secure—so you can prevent, detect, and respond to threats that start in the identity infrastructure. It’s a foundational part of your defense against Identity Security threats, and it’s how you shrink the attack surface before an attacker finds it for you.
At its core, that means regularly auditing and monitoring your environment: cleaning up inactive or orphaned accounts, enforcing strong password policies, and watching user activity. Periodic reviews of AD configurations, user accounts, group memberships, and access permissions surface anomalies and early indicators of compromise before they escalate.
When AD isn’t managed well, the biggest risk is the one you can’t see: no clear picture of who has access to what, and why. Without that visibility, excessive privileges, lateral movement paths, and high-risk accounts go undetected. Stale accounts, unauthorized privileges, and other risky accounts become exactly the openings attackers use.
How Silverfort Identity Security strengthens Active Directory hygiene.
Silverfort natively connects to your existing IAM infrastructure and secures it from within, using its patented Runtime Access Protection (RAP) technology. That gives you one place to discover every identity, analyze where you’re exposed, and enforce security controls in real time—across users, service accounts, and the legacy systems other tools can’t reach.
To strengthen AD hygiene, Silverfort provides complete visibility into every account and maps where each one authenticates. With Identity Security Posture Management (ISPM) capabilities, it surfaces the specific weaknesses attackers look for, including shadow admins, weak encryption, stale and over-privileged service accounts, and prioritizes them by risk with guided remediation for each. The result is a smaller attack surface: fewer exposures for an attacker to exploit for lateral movement or privilege escalation.
5 ways Silverfort helps protect your Active Directory environment
1. Detect shadow admins
Shadow admins are accounts with admin-level privileges no one intended to grant, and are usually the result of Access Control List (ACL) inheritance or nested group membership. The privilege is indirect, so it rarely shows up in a standard access review, and that is why often it gets unnoticed. That makes shadow admins one of the cleanest privilege-escalation paths in AD, and AI-powered adversaries are especially good at finding and chaining them.
How Silverfort helps: Silverfort’s ISPM automatically detects shadow admins as a prioritized exposure. It analyzes accounts across on-prem and cloud to surface the ones holding admin-level permissions they were never meant to have—accounts that would otherwise go unnoticed. From there, you either remove excessive rights or formally document the access.
Customer example: NHS Blood and Transplant used Silverfort to surface shadow admins and unusual authentication patterns across its 7,000-user AD, bringing them under management for DSPT and CAF compliance.
2. Reducing weak encryption and legacy protocols
Weak authentication encryption is one of the quietest risks in AD, because it runs in the background on systems no one has touched in years. Three specific protocols stand out.
- Most teams believe they’ve already dealt with NTLMv1: blocked by Group Policy, case closed. However, Silverfort’s research found that misconfigured applications can still force NTLMv1, so it keeps running while admins assume it’s gone. That matters, because its weak DES encryption cracks in seconds and NTLM relay lets an attacker authenticate as a user without ever knowing the password.
- NTLMv2 is stronger but still legacy: no native MFA support, still exposed to relay and pass-the-hash. It should be treated as a temporary step toward Kerberos. The catch is that NTLM is hard to see; it lingers as a silent Kerberos fallback, and a Group Policy block doesn’t always hold. Read the guide to eliminating NTLM to learn how to find it and phase it out for good.
- RC4 in Kerberos is the bigger, and more urgent, exposure. When Kerberos tickets are encrypted with RC4, they’re vulnerable to Kerberoasting, where any valid domain account can request a service ticket, take it offline, and brute-force it, with no elevated privileges or alerts. It hides on the accounts no one thinks about: service accounts whose passwords predate Advanced Encryption Standard (AES) support, and machine accounts on end-of-life systems that can’t use AES at all. With Microsoft now phasing RC4 out of Kerberos, any dependency you haven’t mapped will start surfacing as authentication failures in production.
How Silverfort helps: ISPM raises Weak Encryption (Users) and Weak Encryption (Servers) indicators wherever RC4 or other weak Kerberos encryption is actually used. Silverfort points you to the accounts most likely to carry it through its Users with Old Passwords and Old Operating Systems views. It monitors NTLMv1 the same way, so you can prioritize eliminating both without capturing a single batch, so you can prioritize eliminating both without capturing a single packet.
For the full RC4 story, including how to find every dependency before enforcement does, read How to plan for RC4 deprecation in Active Directory.
Customer example: University of the Pacific used Silverfort to detect and retire legacy authentication protocols across its four AD domains, cutting the technical debt tied to outdated infrastructure.
3. Find stale accounts and unrotated passwords
Stale accounts are accounts that haven’t been used in a while. The classic example is a former employee whose account was never disabled. They’re easy to miss without authentication monitoring, and service accounts are especially hard to spot because AD doesn’t flag them natively. The real danger is a stale account that still carries admin privileges: dormant, unwatched, and fully valid.
Old credentials make it worse. A password that’s never been changed means any historical breach of that account is still live, and non-expiring passwords are exactly the long-lived credentials that show up in breach databases. Some are set years ago, tied to mission-critical services no one dares to modify.
How Silverfort helps: By continuously analyzing authentication activity, Silverfort automatically identifies stale users with no recent activity. ISPM surfaces the related credential exposures, too: password never changed, non-expiring passwords, and stale accounts with admin privileges. For each of the exposures, Silverfort provides a clear remediation action, from disabling the account to forcing a reset or enforcing rotation.
Customer example: Encora used Silverfort to surface dormant accounts, unrotated passwords, and unmanaged identities across its decentralized AD, giving the security team a prioritized cleanup list for the first time.
4. Disable admins with SPNs
A Service Principal Name (SPN) attached to an admin account is an open invitation to Kerberoasting. An attacker requests the account’s Kerberos ticket, takes the payload offline, and brute-forces the password hash; if that ticket is RC4-encrypted (refer to #2 in our list), the crack happens dramatically faster. The result is a straight path from a basic domain account to a privileged one.
How Silverfort helps: Silverfort detects accounts with SPNs by monitoring authentication events across the network, and ISPM flags Kerberoastable accounts as an exposure. The recommended fix is to review those SPNs and migrate to group Managed Service Accounts (gMSAs) where possible. Silverfort’s behavioral analytics also catch abnormal SPN activity, including unusual access requests or escalation attempts, in real time.
Customer example: In a large healthcare provider’s environment, Silverfort found eight admin accounts with SPNs the customer didn’t know existed. Removing them cut exposure to Kerberoasting.
5. Remove PrintNightmare
PrintNightmare is a critical vulnerability in the Windows Print Spooler service that allows remote code execution and can lead to unauthorized access or system compromise. Even after patching, affected systems can keep generating noisy, abnormal authentications that are easy to miss.
How Silverfort helps: Silverfort detects PrintNightmare by analyzing authentication events and abnormal service behavior, then alerts on every bad Print Spooler authentication for investigation and mitigation. Microsoft’s guidance walks through full remediation, but with Silverfort you can skip the problematic network packet capture entirely, since it surfaces the bad authentications for you.
Customer example: A large US school district detected active PrintNightmare exploitation attempts through Silverfort’s monitoring. After remediation, the organization cut unnecessary authentications by 70%, restoring both security and efficiency.
Treat Active Directory as an Identity Security control surface
Attackers keep exploiting the same weaknesses in AD because it’s too often treated like a legacy system instead of the critical infrastructure it actually is. To get into the right mindset, establishing strong hygiene is the first step. When you can see every identity, every authentication, and proactively remediate every exposure, you shrink the surface an AI adversary can chain through.
Yet hygiene alone assumes you have time to find and fix everything before someone exploits it, and AI attacks make that window of time much shorter. That’s why the same visibility that powers your hygiene program also feeds Silverfort’s runtime controls: MFA, Just-in-Time access, and virtual fencing enforced inline, at the moment of authentication, before access is granted.
You can see where your AD security posture stands in 4 minutes. Take the Active Directory Security Readiness Assessment for a personalized readiness score, benchmarked against your peers, with targeted recommendations you can act upon.
Prefer to talk it through? Reach out to one of our experts.
