Kerberos

How Kerberos Works

Deep Dive into Kerberoasting AttackHacking Articles

AS-REP Roasting

IOC differences between Kerberoasting and AS-REP RoastingMedium

Kerberoasting

RBAC

Detecting Resource-Based Constrained Delegation AbuseSWolfSecurity

Services of Interest:

Possible operation

Service(s)

Description

Related note

PsExec-like file system access

CIFS

Remote execution of commands using PsExec-like utilities or full access to the machine file system.

Windows - Lateral movements [L7] 445 - SMB

WMI

HOST RPCSS

Remote execution of commands through Windows Management Instrumentation (WMI) (Win32_Process class for example).

Windows - Lateral movements

WinRM

Always necessary: HOST HTTP Host dependant: WSMAN RPCSS

PowerShell remoting through Windows Remote Management (WinRM).

Windows - Lateral movements [L7] 5985-5968 - WSMan

Windows services

HOST

Remote creation and/or execution of Windows services.

Windows - Lateral movements

Scheduled tasks

HOST

Remote creation and/or execution of Windows scheduled tasks.

Windows - Lateral movements

DCSync LDAP access

LDAP

LDAP requests, and notably allows, for service tickets to the LDAP service of a Domain Controller, the conduct of replication operations (DCSync).

[ActiveDirectory] ntds.dit dumping

RSAT

CIFS LDAP RPCSS

Use of the PowerShell cmdlets of the Windows Remote Server Administration Tools (RSAT) suite.

[ActiveDirectory] Domain Recon

Exploitation - Kerberos silver tickets | InfoSec Notesnotes.qazeer.io

Post Exploitation - Kerberos golden tickets | InfoSec Notesnotes.qazeer.io

Mitigation:

AD Forest Recovery - Reset the krbtgt passwordMicrosoftLearn

TGTs are encrypted with the KRBTGT hash. Resetting it will invalidate all TGTs within the domain.

Note that the password history value for the KRBTGT account is 2, which means it includes the two most recent passwords. Therefore, to invalidate all TGTs currently in the system, you need to reset the password twice

Important: Be aware that changing the KRBTGT password will affect almost all subsequent Kerberos operations. In particular, all the TGTs that have been issued will be invalid since they were encrypted with the old password. However, all authenticated sessions that have been established to a resource (such as a file share, SharePoint site or Exchange server) are good until the service ticket is required to re-authenticate. Microsoft advises that rebooting a computer is the only reliable way to recover functionality, since this will force both the computer account and the user account to log back in again, which in turn ensures that they get new TGTs encrypted with the new KRBTGT password hash.