Dynamics 365 Customer ServiceApplication · Microsoft

CVE-2025-30391

HIGH · 7.5 CVSS v3.1 Published 2025-04-30
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Improper input validation in Microsoft Dynamics allows an unauthorized attacker to disclose information over a network.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

This is an information disclosure vulnerability in Microsoft Dynamics caused by improper input validation. An unauthenticated attacker can exploit this over a network to gain unauthorized access to sensitive information due to insufficient validation of user-supplied input.

MitigationApply Microsoft security updates for Dynamics when released. In the interim, implement strict input validation on all user-facing fields and follow least-privilege access controls.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Dynamics 365 Customer ServiceApplication
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm Dynamics 365 Customer Service deployment
    Check your Microsoft 365 admin center or Azure portal for installed Dynamics 365 applications. Run Get-InstalledProduct in PowerShell if you have server access, or verify via the Dynamics admin portal that Customer Service is provisioned.
    Affected if Dynamics 365 Customer Service is deployed in your environment
  2. Identify network exposure of Customer Service portal
    Review your firewall rules, Azure application gateway, or load balancer configurations to determine if the Dynamics Customer Service portal/interface is accessible from the internet without authentication.
    Affected if The Customer Service interface is exposed to unauthenticated network access
  3. Check for unauthenticated user-facing endpoints
    Use a web browser or curl command to access common Dynamics Customer Service endpoints (e.g., /cs, /customerService, or your organization's assigned Customer Service URL) without providing credentials.
    Affected if The portal returns content or accepts input without requiring authentication
  4. Verify external user access settings
    In Dynamics 365 admin center, navigate to Customer Service workspace settings and check the 'Portal access' or 'External access' configuration. Inspect the Azure AD B2C or authentication settings to confirm anonymous or unauthenticated access is permitted.
    Affected if External or anonymous user access is enabled on the Customer Service portal

If your organization uses Microsoft Dynamics 365 Customer Service and the portal is accessible to unauthenticated users over the network, you are affected by this vulnerability.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Microsoft security updates for Dynamics when released. In the interim, implement strict input validation on all user-facing fields and follow least-privilege access controls.

Fix this in Dynamics 365 Customer Service Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,980
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-30391 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data