Domain Policy Modification: Domain Trust Modification

ID Name
T1484.001 Group Policy Modification
T1484.002 Domain Trust Modification

Adversaries may add new domain trusts or modify the properties of existing domain trusts to evade defenses and/or elevate privileges. Domain trust details, such as whether or not a domain is federated, allow authentication and authorization properties to apply between domains for the purpose of accessing shared resources.[1] These trust objects may include accounts, credentials, and other authentication material applied to servers, tokens, and domains.

Manipulating the domain trusts may allow an adversary to escalate privileges and/or evade defenses by modifying settings to add objects which they control. For example, this may be used to forge SAML Tokens, without the need to compromise the signing certificate to forge new credentials. Instead, an adversary can manipulate domain trusts to add their own signing certificate.

ID: T1484.002
Sub-technique of:  T1484
Platforms: Azure AD, Windows
Permissions Required: Administrator
Data Sources: Active Directory: Active Directory Object Creation, Active Directory: Active Directory Object Modification, Command: Command Execution
Contributors: Blake Strom, Microsoft 365 Defender
Version: 1.0
Created: 28 December 2020
Last Modified: 11 January 2021

Procedure Examples

ID Name Description
G0016 APT29

APT29 changed domain federation trust settings using Azure AD administrative permissions to configure the domain to accept authorization tokens signed by their own SAML signing certificate.[2]

Mitigations

ID Mitigation Description
M1026 Privileged Account Management

Use the principal of least privilege and protect administrative access to domain trusts.

Detection

Monitor for modifications to domain trust settings, such as when a user or application modifies the federation settings on the domain or updates domain authentication from Managed to Federated via ActionTypes Set federation settings on domain and Set domain authentication.[3] This may also include monitoring for Event ID 307 which can be correlated to relevant Event ID 510 with the same Instance ID for change details.[4][5]

Monitor for PowerShell commands such as: Update-MSOLFederatedDomain –DomainName: "Federated Domain Name", or Update-MSOLFederatedDomain –DomainName: "Federated Domain Name" –supportmultipledomain.[6]

References