Active Directory Kill Chain Attack and Defense

Summary

This document was designed to be a useful, informational asset for those looking to understand the specific tactics, techniques, and procedures (TTPs) attackers are leveraging to compromise active directory and guidance to mitigation, detection, and prevention. And understand Active Directory Kill Chain Attack and Modern Post Exploitation Adversary Tradecraft Activity.

Table of Contents

• Discovery
• Privilege Escalation
• Defense Evasion
• Credential Dumping
• Lateral Movement
• Persistence
• Defense & Detection

Discovery

SPN Scanning

• SPN Scanning – Service Discovery without Network Port Scanning

Data Mining

• A Data Hunting Overview
• Push it, Push it Real Good

User Hunting

• Hidden Administrative Accounts: BloodHound to the Rescue
• Active Directory Recon Without Admin Rights
• Gathering AD Data with the Active Directory PowerShell Module
• Using ActiveDirectory module for Domain Enumeration from PowerShell Constrained Language Mode
• PowerUpSQL Active Directory Recon Functions
• Derivative Local Admin
• Dumping Active Directory Domain Info – with PowerUpSQL!
• Local Group Enumeration
• Attack Mapping With Bloodhound
• Situational Awareness
• Commands for Domain Network Compromise
• A Pentester’s Guide to Group Scoping

LAPS

• Microsoft LAPS Security & Active Directory LAPS Configuration Recon
• Running LAPS with PowerView
• RastaMouse LAPS Part 1 & 2

AppLocker

• Enumerating AppLocker Config

Privilege Escalation

Passwords in SYSVOL & Group Policy Preferences

• Finding Passwords in SYSVOL & Exploiting Group Policy Preferences
• Pentesting in the Real World: Group Policy Pwnage

MS14-068 Kerberos Vulnerability

• MS14-068: Vulnerability in (Active Directory) Kerberos Could Allow Elevation of Privilege
• Digging into MS14-068, Exploitation and Defence
• From MS14-068 to Full Compromise – Step by Step

DNSAdmins

• Abusing DNSAdmins privilege for escalation in Active Directory
• From DNSAdmins to Domain Admin, When DNSAdmins is More than Just DNS Administration

Unconstrained Delegation

• Domain Controller Print Server + Unconstrained Kerberos Delegation = Pwned Active Directory Forest
• Active Directory Security Risk #101: Kerberos Unconstrained Delegation (or How Compromise of a Single Server Can Compromise the Domain)
• Unconstrained Delegation Permissions
• Trust? Years to earn, seconds to break
• Hunting in Active Directory: Unconstrained Delegation & Forests Trusts

Constrained Delegation

• Another Word on Delegation
• From Kekeo to Rubeus
• S4U2Pwnage
• Kerberos Delegation, Spns And More…

Insecure Group Policy Object Permission Rights

• Abusing GPO Permissions
• A Red Teamer’s Guide to GPOs and OUs
• File templates for GPO Abuse

Insecure ACLs Permission Rights

• Exploiting Weak Active Directory Permissions With Powersploit
• Escalating privileges with ACLs in Active Directory
• Abusing Active Directory Permissions with PowerView
• BloodHound 1.3 – The ACL Attack Path Update
• Scanning for Active Directory Privileges & Privileged Accounts
• Active Directory Access Control List – Attacks and Defense
• aclpwn - Active Directory ACL exploitation with BloodHound

Domain Trusts

• A Guide to Attacking Domain Trusts
• It’s All About Trust – Forging Kerberos Trust Tickets to Spoof Access across Active Directory Trusts
• Active Directory forest trusts part 1 - How does SID filtering work?
• The Forest Is Under Control. Taking over the entire Active Directory forest
• Not A Security Boundary: Breaking Forest Trusts
• The Trustpocalypse

DCShadow

• Privilege Escalation With DCShadow
• DCShadow
• DCShadow explained: A technical deep dive into the latest AD attack technique
• DCShadow - Silently turn off Active Directory Auditing
• DCShadow - Minimal permissions, Active Directory Deception, Shadowception and more

RID

• Rid Hijacking: When Guests Become Admins

Microsoft SQL Server

• How to get SQL Server Sysadmin Privileges as a Local Admin with PowerUpSQL
• Compromise With Powerupsql – Sql Attacks

Red Forest

• Attack and defend Microsoft Enhanced Security Administrative

Lateral Movement

Microsoft SQL Server Database links

• SQL Server – Link… Link… Link… and Shell: How to Hack Database Links in SQL Server!
• SQL Server Link Crawling with PowerUpSQL

Pass The Hash

• Performing Pass-the-hash Attacks With Mimikatz
• How to Pass-the-Hash with Mimikatz
• Pass-the-Hash Is Dead: Long Live LocalAccountTokenFilterPolicy

System Center Configuration Manager (SCCM)

• Targeted Workstation Compromise With Sccm
• PowerSCCM - PowerShell module to interact with SCCM deployments

WSUS

• Remote Weaponization of WSUS MITM
• WSUSpendu
• Leveraging WSUS – Part One

Password Spraying

• Password Spraying Windows Active Directory Accounts - Tradecraft Security Weekly #5
• Attacking Exchange with MailSniper
• A Password Spraying tool for Active Directory Credentials by Jacob Wilkin

Automated Lateral Movement

• GoFetch is a tool to automatically exercise an attack plan generated by the BloodHound application
• DeathStar - Automate getting Domain Admin using Empire

• ANGRYPUPPY - Bloodhound Attack Path Automation in CobaltStrike

Defense Evasion

In-Memory Evasion

• Bypassing Memory Scanners with Cobalt Strike and Gargoyle
• In-Memory Evasions Course
• Bring Your Own Land (BYOL) – A Novel Red Teaming Technique

Endpoint Detection and Response (EDR) Evasion

• Red Teaming in the EDR age
• Sharp-Suite - Process Argument Spoofing

OPSEC

• Modern Defenses and YOU!
• OPSEC Considerations for Beacon Commands
• Red Team Tradecraft and TTP Guidance
• Fighting the Toolset

Microsoft ATA & ATP Evasion

• Red Team Techniques for Evading, Bypassing, and Disabling MS Advanced Threat Protection and Advanced Threat Analytics
• Red Team Revenge - Attacking Microsoft ATA
• Evading Microsoft ATA for Active Directory Domination

PowerShell ScriptBlock Logging Bypass

• PowerShell ScriptBlock Logging Bypass

PowerShell Anti-Malware Scan Interface (AMSI) Bypass

• How to bypass AMSI and execute ANY malicious Powershell code
• AMSI: How Windows 10 Plans to Stop Script-Based Attacks
• AMSI Bypass: Patching Technique
• Invisi-Shell - Hide your Powershell script in plain sight. Bypass all Powershell security features

Loading .NET Assemblies Anti-Malware Scan Interface (AMSI) Bypass

• A PoC function to corrupt the g_amsiContext global variable in clr.dll in .NET Framework Early Access build 3694

AppLocker & Device Guard Bypass

• Living Off The Land Binaries And Scripts - (LOLBins and LOLScripts)

Sysmon Evasion

• Subverting Sysmon: Application of a Formalized Security Product Evasion Methodology
• sysmon-config-bypass-finder

HoneyTokens Evasion

• Forging Trusts for Deception in Active Directory
• Honeypot Buster: A Unique Red-Team Tool

Disabling Security Tools

• Invoke-Phant0m - Windows Event Log Killer

Credential Dumping

NTDS.DIT Password Extraction

• How Attackers Pull the Active Directory Database (NTDS.dit) from a Domain Controller
• Extracting Password Hashes From The Ntds.dit File

SAM (Security Accounts Manager)

• Internal Monologue Attack: Retrieving NTLM Hashes without Touching LSASS

Kerberoasting

• Kerberoasting Without Mimikatz
• Cracking Kerberos TGS Tickets Using Kerberoast – Exploiting Kerberos to Compromise the Active Directory Domain
• Extracting Service Account Passwords With Kerberoasting
• Cracking Service Account Passwords with Kerberoasting
• Kerberoast PW list for cracking passwords with complexity requirements

Kerberos AP-REP Roasting

• Roasting AS-REPs

Windows Credential Manager/Vault

• Operational Guidance for Offensive User DPAPI Abuse
• Jumping Network Segregation with RDP

DCSync

• Mimikatz and DCSync and ExtraSids, Oh My
• Mimikatz DCSync Usage, Exploitation, and Detection
• Dump Clear-Text Passwords for All Admins in the Domain Using Mimikatz DCSync

LLMNR/NBT-NS Poisoning

• Pwning with Responder – A Pentester’s Guide
• LLMNR/NBT-NS Poisoning Using Responder

Other

• Compromising Plain Text Passwords In Active Directory

Persistence

Golden Ticket

• Golden Ticket
• Kerberos Golden Tickets are Now More Golden

SID History

• Sneaky Active Directory Persistence #14: SID History

Silver Ticket

• How Attackers Use Kerberos Silver Tickets to Exploit Systems
• Sneaky Active Directory Persistence #16: Computer Accounts & Domain Controller Silver Tickets

DCShadow

• Creating Persistence With Dcshadow

AdminSDHolder

• Sneaky Active Directory Persistence #15: Leverage AdminSDHolder & SDProp to (Re)Gain Domain Admin Rights
• Persistence Using Adminsdholder And Sdprop

Group Policy Object

• Sneaky Active Directory Persistence #17: Group Policy

Skeleton Keys

• Unlocking All The Doors To Active Directory With The Skeleton Key Attack
• Skeleton Key
• Attackers Can Now Use Mimikatz to Implant Skeleton Key on Domain Controllers & BackDoor Your Active Directory Forest

SeEnableDelegationPrivilege

• The Most Dangerous User Right You (Probably) Have Never Heard Of
• SeEnableDelegationPrivilege Active Directory Backdoor

Security Support Provider

• Sneaky Active Directory Persistence #12: Malicious Security Support Provider (SSP)

Directory Services Restore Mode

• Sneaky Active Directory Persistence #11: Directory Service Restore Mode (DSRM)
• Sneaky Active Directory Persistence #13: DSRM Persistence v2

ACLs & Security Descriptors

• An ACE Up the Sleeve: Designing Active Directory DACL Backdoors
• Shadow Admins – The Stealthy Accounts That You Should Fear The Most
• The Unintended Risks of Trusting Active Directory

Tools & Scripts

• PowerView - Situational Awareness PowerShell framework
• BloodHound - Six Degrees of Domain Admin
• Impacket - Impacket is a collection of Python classes for working with network protocols
• aclpwn.py - Active Directory ACL exploitation with BloodHound
• CrackMapExec - A swiss army knife for pentesting networks
• ADACLScanner - A tool with GUI or command linte used to create reports of access control lists (DACLs) and system access control lists (SACLs) in Active Directory
• zBang - zBang is a risk assessment tool that detects potential privileged account threats
• PowerUpSQL - A PowerShell Toolkit for Attacking SQL Server
• Rubeus - Rubeus is a C# toolset for raw Kerberos interaction and abuses
• ADRecon - A tool which gathers information about the Active Directory and generates a report which can provide a holistic picture of the current state of the target AD environment
• Mimikatz - Utility to extract plaintexts passwords, hash, PIN code and kerberos tickets from memory but also perform pass-the-hash, pass-the-ticket or build Golden tickets
• Grouper - A PowerShell script for helping to find vulnerable settings in AD Group Policy.

Ebooks

• The Dog Whisperer’s Handbook – A Hacker’s Guide to the BloodHound Galaxy
• Varonis eBook: Pen Testing Active Directory Environments

Cheat Sheets

• Tools Cheat Sheets - Tools (PowerView, PowerUp, Empire, and PowerSploit)
• DogWhisperer - BloodHound Cypher Cheat Sheet (v2)
• PowerView-3.0 tips and tricks

• PowerView-2.0 tips and tricks

Defense & Detection

Tools & Scripts

• SAMRi10 - Hardening SAM Remote Access in Windows 10/Server 2016
• Net Cease - Hardening Net Session Enumeration
• PingCastle - A tool designed to assess quickly the Active Directory security level with a methodology based on risk assessment and a maturity framework
• Aorato Skeleton Key Malware Remote DC Scanner - Remotely scans for the existence of the Skeleton Key Malware
• Reset the krbtgt account password/keys - This script will enable you to reset the krbtgt account password and related keys while minimizing the likelihood of Kerberos authentication issues being caused by the operation
• Deploy-Deception - A PowerShell module to deploy active directory decoy objects
• dcept - A tool for deploying and detecting use of Active Directory honeytokens
• LogonTracer - Investigate malicious Windows logon by visualizing and analyzing Windows event log
• DCSYNCMonitor - Monitors for DCSYNC and DCSHADOW attacks and create custom Windows Events for these events

Active Directory Security Checks (by Sean Metcalf - @Pyrotek3)

General Recommendations

• Manage local Administrator passwords (LAPS).
• Implement RDP Restricted Admin mode (as needed).
• Remove unsupported OSs from the network.
• Monitor scheduled tasks on sensitive systems (DCs, etc.).
• Ensure that OOB management passwords (DSRM) are changed regularly & securely stored.
• Use SMB v2/v3+
• Default domain Administrator & KRBTGT password should be changed every year & when an AD admin leaves.
• Remove trusts that are no longer necessary & enable SID filtering as appropriate.
• All domain authentications should be set (when possible) to: “Send NTLMv2 response onlyrefuse LM & NTLM.”
• Block internet access for DCs, servers, & all administration systems.

Protect Admin Credentials

• No “user” or computer accounts in admin groups.
• Ensure all admin accounts are “sensitive & cannot be delegated”.
• Add admin accounts to “Protected Users” group (requires Windows Server 2012 R2 Domain Controllers, 2012R2 DFL for domain protection).
• Disable all inactive admin accounts and remove from privileged groups.

Protect AD Admin Credentials

• Limit AD admin membership (DA, EA, Schema Admins, etc.) & only use custom delegation groups.
• ‘Tiered’ Administration mitigating credential theft impact.
• Ensure admins only logon to approved admin workstations & servers.
• Leverage time-based, temporary group membership for all admin accounts

Protect Service Account Credentials

• Limit to systems of the same security level.
• Leverage “(Group) Managed Service Accounts” (or PW >20 characters) to mitigate credential theft (kerberoast).
• Implement FGPP (DFL =>2008) to increase PW requirements for SAs and administrators.
• Logon restrictions – prevent interactive logon & limit logon capability to specific computers.
• Disable inactive SAs & remove from privileged groups.

Protect Resources

• Segment network to protect admin & critical systems.
• Deploy IDS to monitor the internal corporate network.
• Network device & OOB management on separate network.

Protect Domain Controllers

• Only run software & services to support AD.
• Minimal groups (& users) with DC admin/logon rights.
• Ensure patches are applied before running DCPromo (especially MS14-068 and other critical patches).
• Validate scheduled tasks & scripts.

Protect Workstations (& Servers)

• Patch quickly, especially privilege escalation vulnerabilities.
• Deploy security back-port patch (KB2871997).
• Set Wdigest reg key to 0 (KB2871997/Windows 8.1/2012R2+): HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSecurityProvidersWdigest
• Deploy workstation whitelisting (Microsoft AppLocker) to block code exec in user folders – home dir & profile path.
• Deploy workstation app sandboxing technology (EMET) to mitigate application memory exploits (0-days).

Logging

• Enable enhanced auditing
• “Audit: Force audit policy subcategory settings (Windows Vista or later) to override audit policy category settings”
• Enable PowerShell module logging (“*”) & forward logs to central log server (WEF or other method).
• Enable CMD Process logging & enhancement (KB3004375) and forward logs to central log server.
• SIEM or equivalent to centralize as much log data as possible.
• User Behavioural Analysis system for enhanced knowledge of user activity (such as Microsoft ATA).

Security Pro’s Checks

• Identify who has AD admin rights (domain/forest).
• Identify who can logon to Domain Controllers (& admin rights to virtual environment hosting virtual DCs).
• Scan Active Directory Domains, OUs, AdminSDHolder, & GPOs for inappropriate custom permissions.
• Ensure AD admins (aka Domain Admins) protect their credentials by not logging into untrusted systems (workstations).
• Limit service account rights that are currently DA (or equivalent).

Detection

Resources

• Reducing the Active Directory Attack Surface
• Securing Domain Controllers to Improve Active Directory Security
• Securing Windows Workstations: Developing a Secure Baseline
• Implementing Secure Administrative Hosts
• Privileged Access Management for Active Directory Domain Services
• Awesome Windows Domain Hardening
• Best Practices for Securing Active Directory
• Introducing the Adversary Resilience Methodology — Part One
• Introducing the Adversary Resilience Methodology — Part Two
• Mitigating Pass-the-Hash and Other Credential Theft, version 2
• Configuration guidance for implementing the Windows 10 and Windows Server 2016 DoD Secure Host Baseline settings
• Monitoring Active Directory for Signs of Compromise
• Detecting Lateral Movement through Tracking Event Logs
• Kerberos Golden Ticket Protection Mitigating Pass-the-Ticket on Active Directory
• Overview of Microsoft’s “Best Practices for Securing Active Directory”
• The Keys to the Kingdom: Limiting Active Directory Administrators
• Protect Privileged AD Accounts With Five Free Controls
• The Most Common Active Directory Security Issues and What You Can Do to Fix Them
• Event Forwarding Guidance
• Planting the Red Forest: Improving AD on the Road to ESAE
• Detecting Kerberoasting Activity
• Security Considerations for Trusts
• Advanced Threat Analytics suspicious activity guide
• Protection from Kerberos Golden Ticket
• Windows 10 Credential Theft Mitigation Guide
• Detecting Pass-The- Ticket and Pass-The- Hash Attack Using Simple WMI Commands
• Step by Step Deploy Microsoft Local Administrator Password Solution
• Active Directory Security Best Practices
• Finally Deploy and Audit LAPS with Project VAST, Part 1 of 2
• Windows Security Log Events
• Talk Transcript BSidesCharm Detecting the Elusive: Active Directory Threat Hunting
• Preventing Mimikatz Attacks
• Understanding “Red Forest” - The 3-Tier ESAE and Alternative Ways to Protect Privileged Credentials
• AD Reading: Active Directory Backup and Disaster Recovery
• Ten Process Injection Techniques: A Technical Survey Of Common And Trending Process Injection Techniques
• Hunting For In-Memory .NET Attacks
• Mimikatz Overview, Defenses and Detection
• Trimarc Research: Detecting Password Spraying with Security Event Auditing
• Hunting for Gargoyle Memory Scanning Evasion
• Planning and getting started on the Windows Defender Application Control deployment process
• Preventing Lateral Movement Using Network Access Groups
• How to Go from Responding to Hunting with Sysinternals Sysmon
• Windows Event Forwarding Guidance
• Threat Mitigation Strategies: Part 2 – Technical Recommendations and Information

License

To the extent possible under law, Rahmat Nurfauzi "@infosecn1nja" has waived all copyright and related or neighboring rights to this work.