AD Starter Scan - Kerberos Krbtgt

medium Nessus Plugin ID 150484
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

KDC last password change is too old.

Description

Every Active Directory domain includes a special account called KRBTGT. This account holds the Kerberos master key, protecting all other secrets in the domain. Hence, it must be protected at all costs and renewed regularly. This plugin checks if the master key is set to be renewed at least once every two years.

Note: This plugin is part of the Active Directory Starter Scan Template and is meant to be used for preliminary analysis of AD hosts. For more information on the issues discovered by the Active Directory Starter Scan plugins, please refer to this blog post - https://www.tenable.com/blog/new-in-nessus-find-and-fix-these-10-active-directory-misconfigurations

Solution

The KRBTGT password must be changed by following a precise sequence of operations. If it is not done properly, some domain controllers may lose the ability to authenticate against other domain controllers. Microsoft provides an official procedure and helper script.

See Also

http://www.nessus.org/u?79a46bf7

https://adsecurity.org/?p=483

https://github.com/microsoft/New-KrbtgtKeys.ps1

http://www.nessus.org/u?d5c4c81f

Plugin Details

Severity: Medium

ID: 150484

File Name: adsi_kerberos_krbtgt.nbin

Version: 1.9

Type: local

Agent: windows

Family: Windows

Published: 7/29/2021

Updated: 9/16/2021

Dependencies: adsi_enum.nbin

Risk Information

CVSS Score Source: manual

CVSS Score Rationale: Score based on an in-depth analysis by tenable.

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:N

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Vulnerability Information

CPE: cpe:/a:microsoft:active_directory

Required KB Items: Secret/adsi/username/0, Secret/adsi/password/0, adsi/host/0, adsi/domain/0, adsi_enum_users_and_groups/available