Blog

AD Security, Hardening and Project Practice

Technical notes on Active Directory security, hardening, incident readiness and measurable risk reduction.

Deploy AppLocker with Group Policy: from audit to a defensible allowlist

AppLocker reduces the freely executable software surface on Windows systems. A defensible rollout starts in audit mode, separates device classes and rule collections, and enforces a maintainable allowlist only after the telemetry has been reviewed.

Active DirectoryHardeningAppLockerApplication ControlGroup Policy

Control machine account password age: keep domain trust predictable

Domain members normally rotate their machine account password every 30 days. A sound AD baseline preserves that behavior, detects exceptions and treats stale passwords as lifecycle evidence rather than an automatic trust failure.

Active DirectoryHardeningMachine AccountsGroup PolicyNetlogon

Secure Microsoft Entra Connect: operate the identity bridge as Tier 0

Microsoft Entra Connect links on-premises Active Directory and Entra ID through powerful accounts, rules and write paths. The sync server therefore belongs in the control plane, with narrow administration, minimum permissions, guarded exports and tested recovery.

Active DirectoryHardeningMicrosoft Entra IDHybrid IdentityTier 0

Harden UNC paths: protect SYSVOL and NETLOGON properly

SYSVOL and NETLOGON look ordinary, but they are critical AD paths. Hardened UNC Paths enforce Kerberos-based server authentication and SMB integrity instead of letting Group Policy load across weak paths.

Active DirectoryHardeningGroup PolicySMBUNC Paths

Disable WinRM Basic Auth: remote administration without password fallback

WinRM is useful for Windows administration, but Basic Auth and unencrypted fallbacks do not belong in an AD baseline. Kerberos, narrow listeners, no stored admin credentials and clear exceptions are the better operating state.

Active DirectoryHardeningWinRMPowerShell RemotingKerberos

Restrict RDP logon on Domain Controllers

Domain Controllers are not normal administration servers. RDP should only be possible for clearly defined Tier-0 administrators, from controlled networks and with visible logging.

Active DirectoryHardeningDomain ControllersRDPTier 0

Block anonymous enumeration: stop leaking AD inventory

Anonymous queries in older Windows environments often reveal more inventory than expected. A clean baseline limits null sessions, SAMR, named pipes, shares and guest paths without blindly breaking legacy systems.

Active DirectoryHardeningAnonymous EnumerationSAMRSMB

Clean up SID History: remove migration leftovers from AD tokens

sIDHistory is useful during domain migrations, but often remains as a quiet authorization anchor afterwards. A clean removal needs inventory, owners, access testing and a controlled pilot.

Active DirectoryHardeningSID HistoryMigrationTier 0

Block interactive logon for service accounts

Service accounts should run workloads, not become convenient shared users. Interactive sign-in, RDP, and local logon should be blocked in a controlled way without breaking legitimate service and batch workloads.

Active DirectoryHardeningService AccountsGPORDP

Hardening AD CS: treat certificates as Tier-0 risk

AD CS indirectly controls who can authenticate as whom. If templates, enrollment rights and CA operations are unmanaged, PKI can become a domain takeover path.

Active DirectoryHardeningAD CSPKITier 0

Rotate the krbtgt password: invalidate Kerberos tickets without breaking logons

The krbtgt account is the foundation of Kerberos ticket integrity in an AD domain. Rotating it is not a casual “password change” — it’s a controlled operation with replication, ticket lifetimes, and dependencies. This is a practical, low-drama rollout approach, including limits and a project checklist.

Active DirectoryHardeningKerberoskrbtgtWindows

Enable the AD Recycle Bin: roll back deletions quickly and cleanly

Deleted users, groups, or OUs are a very real operational risk — and classic backup restores are often too heavy for the job. With the AD Recycle Bin you get a pragmatic, auditable restore option, if you roll it out properly.

Active DirectoryHardeningRecoveryWindows

Disable and remove SMBv1: get legacy SMB out of your network

SMBv1 has no place in modern AD environments — yet in practice it’s often still enabled somewhere. This is a controlled, low-drama way to remove SMBv1 from clients, servers, and images without breaking operations.

Active DirectoryHardeningSMBSMBv1Windows

Disable LLMNR & NBT-NS: make name resolution DNS-only again

When DNS fails, Windows often falls back to LLMNR or NetBIOS (NBT-NS) — multicast/broadcast instead of authority. That’s unnecessary attack surface and creates confusing authentication noise. Here’s a controlled, project-friendly rollout.

Active DirectoryHardeningLLMNRNetBIOSDNS

Disable WDigest: reduce plaintext credential exposure in LSASS

WDigest is a legacy mechanism that can be re-enabled by old images, GPOs, or troubleshooting workarounds. Here’s how to verify the current state, enforce a robust baseline, and keep plaintext passwords out of LSASS.

Active DirectoryHardeningWDigestLSASS

Disable the Print Spooler on Domain Controllers

Domain Controllers are Tier 0. Print services don’t belong there. This is how to disable the Print Spooler safely, handle exceptions, and make the control auditable.

Active DirectoryHardeningPrint SpoolerTier 0

Set MachineAccountQuota to 0

When regular users can create computer objects, unnecessary attack paths appear. MachineAccountQuota should be a decision, not an inherited default.

Active DirectoryDelegationHardening

Protected Users for Tier 0

Protected Users is powerful, but not for broad rollout. Its value depends on carefully selected accounts and tested admin paths.

Active DirectoryTier 0Hardening

Disable NTLMv1, Reduce NTLM

NTLM is rarely removed in one step. A reliable approach starts with audit data, clear exceptions and a Kerberos target state.

Active DirectoryNTLMHardening

Make SMB Signing the Baseline

SMB signing does not secure every file share by itself, but it removes an important lever from relay-style attacks.

Active DirectorySMBHardening

Rolling Out Windows LAPS Properly

LAPS reduces lateral movement only when scope, permissions, rotation and DSRM recovery are planned deliberately.

Active DirectoryLAPSHardening

CVSS Above 9: Why Triage Matters More Than Panic

Critical vulnerabilities must be assessed quickly, but always in the context of exposure, exploitability and compensating controls.

CVSSVulnerability ManagementCritical Infrastructure

Active Directory Security as a Project Building Block

Why AD security should not be treated as a one-off check, but as a prioritized project building block for risk reduction, audit readiness and incident readiness.

Active DirectorySecurity AdvisoryPentesting

EDR: Detection Tuning Instead of Tool Hope

EDR creates value only through clean policies, meaningful exceptions, incident processes and tests against realistic attack techniques.

EDRDetectionIncident Response

Implementing Zero Trust Pragmatically

Zero Trust works better as an architecture principle than as a product category: identities, devices, segmentation and visibility must align.

Zero TrustArchitectureMicrosoft Security

Security Awareness Needs Technical Controls

Awareness reduces risk sustainably only when technical controls, reporting paths and measurable improvements are included.

Security AwarenessPhishingDefensive Security