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Insecure authentication method - NTLM


The application uses the Legacy NTLM authentication protocol which can be vulnerable to several security flaws, including Relay attacks, Man in the Middle and brute force to obtain valid challenge results.


Obtain valid challenges to impersonate application users.


Avoid and restrict the use of NTLM as authentication mechanism, in favor of more recent and secure alternatives such as Kerberos, Smart Cards, OAuth, Bearer Authentication, forms, JWT, among others.


Anonymous attacker from adjacent network performing a MitM.

Expected Remediation Time

⌚ 120 minutes.


Default score using CVSS 3.1. It may change depending on the context of the vulnerability.


  • Attack vector: A
  • Attack complexity: H
  • Privileges required: N
  • User interaction: R
  • Scope: U
  • Confidentiality: L
  • Integrity: L
  • Availability: N


  • Exploit code madurity: P
  • Remediation level: O
  • Report confidence: C


  • Vector string: CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C
  • Score:
    • Base: 3.7
    • Temporal: 3.4
  • Severity:
    • Base: Low
    • Temporal: Low

Code Examples

Compliant code

The server configuration uses a safe authentication mechanism

adminSecurity: active
authMode: Kerberos

Non compliant code

The server configuration file contains NTML authentication protocol

adminSecurity: active
authMode: NTLM