Tenant has all External organizations allowed to collaborate as Connected Organization

Overview

Access packages configured to allow “All users” instead of specific connected organizations expose your organization to uncontrolled external access. Threat actors can exploit this by requesting access through compromised external accounts from unauthorized organizations, bypassing the principle of least privilege. This enables initial access, reconnaissance, privilege escalation, and lateral movement within your environment.

Remediation

• Define trusted organizations as connected organizations
• Configure access packages to only allow specific connected organizations

Run it

The check runs as part of the whole assessment, with the ZeroTrustAssessment module installed:

Install-Module ZeroTrustAssessment -Scope CurrentUser
Connect-Maester
Invoke-Maester -Pack ZTA -SkipBuiltIn

Leave out -SkipBuiltIn to run Maester’s own checks in the same run.

About this check

Severity	Medium
Effort to fix	Medium
Impact on users	Medium
Pillar	Identity
Category	Access control
Product	Entra ID
Feature	Identity Governance
Area	External access and sharing
ATT&CK	T1199 Trusted Relationship, T1078.004 Cloud Accounts
Licence	P2, Governance
Tenant	Workforce, External

Product, feature, area and ATT&CK are Maester’s: the assessment does not record them, so Maester keeps them in the pack’s taxonomy.json.

A Microsoft check, part of the Zero Trust Assessment pack. Text from ZeroTrustAssessment 3.1.0, © Microsoft, MIT licence.