CQURE Hacks #68: NTLM Relay Attacks Explained and Why It’s Time to Phase Out NTLM

Source: CQURE Academy

Author: Daniel

URL: https://cqureacademy.com/blog/ntlm-relay-attacks-and-why-to-phase-out/

CQURE Hacks #68: NTLM Relay Attacks Explained and Why It’s Time to Phase Out NTLM

ONE SENTENCE SUMMARY:

Disabling NTLM authentication prevents relay attacks by forcing the use of Kerberos, enhancing security across Active Directory environments.

MAIN POINTS:

1. Initially, NTLM authentication setting is disabled on the Domain Controller, allowing relay attacks.
2. Attacker uses Responder and ntlmrelayx tools on Kali Linux to perform NTLM relay.
3. Successful relay allows attacker access with credentials as CQURE\Administrator for further actions.
4. Switching Group Policy to “Deny All” disables NTLM, blocking relay attacks.
5. Kerberos authentication replaces NTLM, removing vulnerability to relay attacks.
6. Demonstration highlights reduced NTLM attack surface when disabled.
7. Phasing out NTLM requires identifying systems dependent on it.
8. CQURE NTLM Phase-out Guide aids Active Directory NTLM replacement.
9. New Advanced Windows Security Course 2026 registration is open.
10. CQURE Hacks video demonstrates NTLM relay attack and mitigation steps.

TAKEAWAYS:

1. Disabling NTLM eliminates relay attack vulnerability.
2. Kerberos provides a more secure authentication method.
3. Identify and audit NTLM-dependent systems before disabling.
4. Proper planning is essential for a smooth NTLM phase-out.
5. Educational resources and courses can aid in transitioning to secure methods.