When a penetration tester obtains an NTLM hash from a legacy Windows machine, they need to use a tool that can leverage this hash for further attacks, such as pass-the-hash attacks, or for cracking the hash. Here’s a breakdown of the options:

Option A: Responder

Responder is primarily used for poisoning LLMNR, NBT-NS, and MDNS to capture hashes, but not for leveraging NTLM hashes obtained post-exploitation.

Option B: Hydra

Hydra is a password-cracking tool but not specifically designed for NTLM hashes or pass-the-hash attacks.

Option C: BloodHound

BloodHound is used for mapping out Active Directory relationships and identifying potential attack paths but not for using NTLM hashes directly.

Option D: CrackMapExec

CrackMapExec is a versatile tool that can perform pass-the-hash attacks, execute commands, and more using NTLM hashes. It is designed for post-exploitation scenarios involving NTLM hashes.

References from Pentest:

Forge HTB: Demonstrates the use of CrackMapExec for leveraging NTLM hashes to gain further access within a network​​.

Horizontall HTB: Shows how CrackMapExec can be used for various post-exploitation activities, including using NTLM hashes to authenticate and execute commands​​.

Conclusion:

Option D, CrackMapExec, is the most suitable tool for continuing the attack using an NTLM hash. It supports pass-the-hash techniques and other operations that can leverage NTLM hashes effectively.

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