Tag: KerberosSilverTicket

Dec 31

Cracking Kerberos TGS Tickets Using Kerberoast – Exploiting Kerberos to Compromise the Active Directory Domain

Microsoft’s Kerberos implementation in Active Directory has been targeted over the past couple of years by security researchers and attackers alike. The issues are primarily related to the legacy support in Kerberos when Active Directory was released in the year 2000 with Windows Server 2000. This legacy support is enabled when using Kerberos RC4 encryption …

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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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Nov 18

MS14-068: Vulnerability in (Active Directory) Kerberos Could Allow Elevation of Privilege

Active Directory leverages the Kerberos protocol for authentication. The vulnerability patches an issue with how the Domain Controller validates group membership in Kerberos tickets (hint: the ticket is always validated by the DC if the checksum is set to certain values). Microsoft KB3011780 patches this issue. According to Microsoft: “When this security bulletin was issued, …

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Oct 30

BlueHat 2014 Slides: Reality Bites – The Attacker’s View of Windows Authentication and Post-exploitation

Each year, Microsoft invites security researchers (aka hackers) to speak to Microsoft employees about security issues. One of the most interesting talks listed at “BlueHat” 2014 was the one by the “Pass-the-Hash” experts, Chris Campbell, Bejamin Delpy, and Skip Duckwall. This talk will focus on the how Windows authentication works in the real world and …

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