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Tag: rubeus

Not A Security Boundary: Breaking Forest Trusts

For years Microsoft has stated that the forest was the security boundary in Active Directory. For example, Microsoft’s “What Are Domains and Forests?” document (last updated in 2014) has a “Forests as Security Boundaries” section which states (emphasis added): Each forest is a single instance of the directory, the top-level Active Directory container, and a security boundary for all objects that are located in the forest. This security boundary defines the scope of authority of the administrators. In general, a security boundary is defined by the top-level container for which no administrator external to the container can take control away…

Another Word on Delegation

Every time I think I start to understand Active Directory and Kerberos, a new topic pops up to mess with my head. A few weeks ago, @elad_shamir contacted @tifkin_ and myself with some ideas about resource-based Kerberos constrained delegation. Thanks to Elad’s ideas, the great back and forth, and his awesome pull request to Rubeus, we now understand this attack vector and have a tool to abuse it. We also now have something @_wald0, @cptjesus, and I have wanted for a long while- an ACL-based computer object takeover primitive! But first, some background on delegation and a dive into its resource-based flavor. Delegation…

Rubeus – Now With More Kekeo

Rubeus, my C# port of some of features from @gentilkiwi‘s Kekeo toolset, already has a few new updates in its 1.1.0 release, and another new feature in its 1.2.0 release. This post will cover the main new features as well as any miscellaneous changes, and will dive a bit into the coolest new features- fake delegation TGTs and Kerberos based password changes. As before, I want to stress that @gentilkiwi is the originator of these techniques, and this is project is only a reimplementation of his work. If it wasn’t for Kekeo, I would never have been able to figure out these…

From Kekeo to Rubeus

Kekeo, the other big project from Benjamin Delpy after Mimikatz, is an awesome code base with a set of great features. As Benjamin states, it’s external to the Mimikatz codebase because, “I hate to code network related stuff ; It uses an external commercial ASN.1 library inside.“ Kekeo provides (feature list not complete): The ability to request ticket-granting-tickets (TGTs) from user hashes (rc4_hmac/aes128_cts_hmac_sha1/aes256_cts_hmac_sha1) as well as applying requested TGTs to the current logon session. This provides an alternative to Mimikatz’ “over-pass-the-hash” that doesn’t manipulate LSASS’ memory and doesn’t require administrative privileges. The ability to request service tickets from existing TGTs. The only S4U…