cyber revision

Windows & Active Directory quick reference

Security event IDs to know, the common credential attacks against a domain and the commands you reach for when investigating.

Key Windows Security event IDs

Logged to the Security event log. These are the ones that come up constantly in investigations.

Event ID What it records
4624 A successful account logon
4625 A failed account logon
4688 A new process was created
4720 A user account was created
4768 A Kerberos authentication ticket (TGT) was requested
4776 The domain controller attempted to validate credentials over NTLM

The logon type field on 4624 and 4625 matters: type 2 is interactive, type 3 is network, type 10 is remote interactive (RDP).

Common AD credential attacks

Attack What the attacker does
Pass the Hash Reuses a captured NTLM hash to authenticate without ever knowing the plaintext password.
Kerberoasting Requests service tickets for accounts with an SPN, then cracks the ticket offline for the service password.
AS-REP Roasting Targets accounts with Kerberos pre-authentication disabled, capturing a crackable AS-REP.
Golden Ticket Forges a TGT using the stolen krbtgt account hash, minting access to anything in the domain.
Silver Ticket Forges a service ticket using a single service account hash, granting access to that one service.
DCSync Impersonates a domain controller and asks for password data through the replication protocol.

Investigation commands

Command What it shows
net user <name> Account details, group membership and last logon for a local or domain user
net group "Domain Admins" /domain Members of a domain group
whoami /all The current token: user, groups, privileges and SID
Get-ADUser -Filter * -Properties * Detailed AD user objects via the ActiveDirectory PowerShell module
nltest /dclist:<domain> Lists the domain controllers for a domain