Tag: mimikatz

Nov 17

How Attackers Use Kerberos Silver Tickets to Exploit Systems

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 …

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Sep 25

Sneaky Active Directory Persistence #13: DSRM Persistence v2

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 at DerbyCon (2015). I also presented and posted on DSRM as a persistence method previously. Complete list of Sneaky Active …

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Sep 25

Mimikatz DCSync Usage, Exploitation, and Detection

Note: I presented on this AD persistence method at DerbyCon (2015). A major feature added to Mimkatz this summer is “DCSync” which effectively “impersonates” a Domain Controller and requests account password data from the targeted Domain Controller. DCSync was written by Benjamin Delpy and Vincent Le Toux. The exploit method prior to DCSync was to …

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Sep 16

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

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 Security …

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Sep 10

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

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 …

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Aug 07

Kerberos Golden Tickets are Now More Golden

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, …

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Jul 15

It’s All About Trust – Forging Kerberos Trust Tickets to Spoof Access across Active Directory Trusts

In early 2015, I theorized that it’s possible to forge inter-realm (inter-trust) Kerberos tickets in a similar manner to how intra-domain TGTs (Golden Tickets) and TGSs (Silver Tickets) are forged. Around the same time, Benjamin Delpy updated Mimikatz to dump trust keys from a Domain Controller. Soon after, Mimikatz gained capability to forge inter-realm trust …

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May 11

Detecting Mimikatz Use

Benjamin Delpy published some YARA rules in detecting Mimikatz use in your environment. More information on Mimikatz capability is in the “Unofficial Mimikatz Guide & Command Reference” on this site. YARA is described as: YARA is a tool aimed at (but not limited to) helping malware researchers to identify and classify malware samples. With YARA …

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May 08

Microsoft Ignite 2015 Security Sessions

Microsoft retired several conferences this year (TechEd, MEC, MMC, etc) and merged them into a single mega-conference called Microsoft Ignite 2015. About 23,000 people (~29k including all staff and support personnel) converged on the McCormick Place Conference Center in Chicago, IL during the week of May 4th (May the Fourth be With You!). I recently …

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Feb 18

Interesting KRBTGT Password Reset Behavior

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 …

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