EIDTNT-005: External Collaboration Settings

Platform
Entra ID / M365
Category
Entra ID Tenant Configuration
Severity
High
Zero Trust pillar
Governance (weight 2)
Golden fixtures
3
Branch coverage
Observed: fixtures prove the verdicts they exercise
Provenance
baseline

What it checks

External collaboration settings define the scope of domains from which guest users can be invited and which external organizations can collaborate with the tenant. Without domain restrictions, guests can be invited from any external organization, including competitors, sanctioned entities, or attacker-controlled tenants. Domain allowlists or blocklists should be configured to limit collaboration to approved partner organizations and prevent unauthorized external access.

Recommended value

External collaboration restricted to specific allowed domains with a deny list for known high-risk domains

Remediation

Navigate to Entra ID > External Identities > External collaboration settings and configure collaboration restrictions. Implement either an allowlist of approved partner domains or a blocklist of known high-risk and competitor domains based on your organization's collaboration model. Review and update the domain list quarterly to reflect changes in partner relationships and ensure that collaboration restrictions align with data classification and information sharing policies.

Fixture-proven verdicts

Every verdict below is proven by a golden fixture in the module's gating test suite. This table derives from the last green run; it cannot be edited by hand.

Verdict scenarios for EIDTNT-005
ScenarioExpected verdict
cleanPASS
known-badFAIL
no-dataNot Assessed

Framework mappings

CISA SCuBA
MS.AAD.8.3v1
NIST SP 800-53
AC-20
CIS M365 Benchmark
1.3.1