Nov 17 2015
Usually Golden Tickets (forged Kerberos TGTs) get all the press, but this post is about Silver Tickets and how attackers use them to exploit systems. I have talked about how Silver Tickets can be used to persist and even re-exploit an Active Directory enterprise in presentations at security conferences this year. This post continues this …
Sep 10 2015
The content in this post describes a method by which an attacker could persist administrative access to Active Directory after having Domain Admin level rights for 5 minutes. I presented on this AD persistence method in Las Vegas at DEF CON 23 (2015). Complete list of Sneaky Active Directory Persistence Tricks posts The Directory …
Aug 07 2015
At my talk at Black Hat USA 2015, I highlighted new Golden Ticket capability in Mimikatz (“Enhanced Golden Tickets”). This post provides additional detailed on “enhanced” Golden Tickets. Over the past few months, I researched how SID History can be abused in modern enterprises. As part of this research, I reached out to Benjamin Delpy, …
May 07 2015
At the Microsoft Ignite conference this week, there are several sessions covering Windows 10 features. One of biggest changes in Windows 10 is the new credential management method and the related “Next Generation Credential”, now named Microsoft Passport. There hasn’t been much information on how the new credential system works, so I challenged myself to …
May 03 2015
Over the last 6 months, I have been researching forged Kerberos tickets, specifically Golden Tickets, Silver Tickets, and TGTs generated by MS14-068 exploit code (a type of Golden Ticket). I generated forged Kerberos tickets using Mimikatz (Mimikatz Command Reference) and MS14-068 exploits and logged the results. Over the course of several weeks, I identified anomalies …
Feb 18 2015
Following up on Twitter conversations (@passingthehash, @scriptjunkie1, gentilkiwi, etc) on the new KRBTGT Password Reset Script and Skip Duckwall’s (@passingthehash) blog post on how KRBTGT password changes work. Microsoft KB2549833 states that the KRBTGT password is set automatically to a random string when a new password is entered. This occurs because there is special logic …
Feb 11 2015
On February’s Patch Tuesday (2/11/2015), Microsoft released two patches that fix issues with the way Group Policy is processed by the client. Interestingly enough, one of these vulnerabilities (MS15-014) makes the other one (MS15-011) not only feasible, but quite capable. The Attack Scenario: An attacker leverages the vulnerability described in MS15-014 to prevent/stop Group Policy …
Jan 19 2015
Once an attacker has gained Domain Admin rights to your Active Directory environment, there are several methods for keeping privileged access. Skeleton Key is an ideal persistence method for the modern attacker. More information on Skeleton Key is in my earlier post. Note that the behavior documented in this post was observed in a lab …
Jan 16 2015
Dell SecureWorks posted about the Skeleton Key malware discovered at a customer site. The Skeleton Key malware is installed on one or multiple Domain Controllers running a supported 64bit OS. The malware “patches” the security system enabling a new master password to be accepted for any domain user, including admins. This enables the attacker to …