Posts Tagged: Kerberos

Inside Kerberos – 7: Wrap up

17th May, 2018

Alright, we’ve covered a lot of ground, but let’s wrap up by grabbing our original questions and answering the 1. Why is there a problem with SIDHistory and Domain Local Groups, and exactly what is the problem? We’ve seen that Domain Local groups can have sid-history applied from one domain to another, this allows for […]

Inside Kerberos – 6: Conversations

10th May, 2018

We have covered a lot of ground so far, and we have touched on the Kerberos conversations that go on, but let’s take a deeper look at exactly how these messages are made up and how they are protected. Elements to protect the transmission Secret Keys Secret keys are stored inside the Security Account Manager […]

Inside Kerberos – 5: Tokens

3rd May, 2018

Alright then, we’ve covered SIDs, SIDHistory, and Tickets.  Let’s move onto Access Tokens. Privilege Access Certificate The Privilege Access Certificate or PAC is a Microsoft extension to Kerberos utilizing the Authorization Data field in the tickets.  This is sometimes referred to as the Access Token, however strictly speaking the Access Token is the structure generated […]

Inside Kerberos – 4: Tickets

25th April, 2018

Ok I think we have talked enough about SIDs in the previous two parts on SIDs and SIDHistory.  Let’s move on to Kerberos tickets… Luckily in Kerberos there are really only two tickets (which confusingly are sometimes also referred to as Tokens) Ticket Granting Ticket (TGT) Service Ticket (ST) Both of these tickets are issued […]

Inside Kerberos – 3: SIDHistory

19th April, 2018

In this blog we will be exploring SID History, and it follows on from Part 1 which gave an overview of Kerberos, and Part 2 which was all about SIDs. The attribute sid-history has been there right since Windows 2000 and is used to store all of the SIDs that an object has had.   […]

Inside Kerberos – 2: SIDs

12th April, 2018

In Part 1 we set the scene in regards to how Kerberos works at a high level, so let’s now get down and dirty with Security Identifiers (SIDs) What is a Security Identifier (SID)? From MSDN: “A security identifier (SID) is a unique value of variable length used to identify a trustee. Each account has […]

Inside Kerberos – 1: Overview

5th April, 2018

I recently did some work at a client to help migrate them to a new Active Directory.  While setting up the migration including password and SidHistory syncs I told them to be careful of Domain Local Groups which can cause issues if users are nested directly in them.  Now I knew this was true, but […]