D365 F&O MCP Server: Official Azure one-click deployment ships with authentication disabled by default, exposing proprietary X++ source over the public internet
Summary
| CVE | CVE-2026-114123 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-21 17:18:25 UTC |
| Updated | 2026-10-21 17:18:25 UTC |
| Description | D365 F&O MCP Server is a Model Context Protocol server for querying Dynamics 365 Finance & Operations X++ code and metadata. Prior to version 1.11.0, the officially documented Azure one-click deployment uses infrastructure/azuredeploy.json and infrastructure/main.bicep to default the apiKey parameter to an empty string and pass it to the App Service API_KEY setting. With API_KEY unset or empty, src/middleware/apiKeyAuth.ts passes requests through without authentication, while src/index.ts binds the HTTP listener to 0.0.0.0 by default. If the deployer leaves the optional key blank and does not add separate network restrictions or upstream authentication, the resulting public App Service allows unauthenticated JSON-RPC tools/call requests to /mcp. The deployment's MCP_SERVER_MODE=read-only setting does not prevent anonymous access to read/search tools, including search, get_object_info, batch_get_info, extension_info, security_info, find_references, and find_event_handlers, exposing indexed proprietary X++ source snippets and metadata. Exposed information can include business logic, extension and event-handler wiring, security-role and privilege structure, and labels originally indexed from PackagesLocalDirectory. Deployments protected by a configured API key, effective upstream authentication, or network restrictions preventing attacker access are outside this unauthenticated exposure scenario. This issue is fixed in version 1.11.0. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Problem Types: CWE-306 | CWE-1188 | CWE-306 CWE-306: Missing Authentication for Critical Function | CWE-1188 CWE-1188: Insecure Default Initialization of Resource
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
NoneAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Dynamics365ninja | D365fo-mcp-server | affected < 1.11.0 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/dynamics365ninja/d365fo-mcp-server/security/advisories/GHSA-8... | [email protected] | github.com | |
| github.com/dynamics365ninja/d365fo-mcp-server/commit/384394a81e1c6c1e014... | [email protected] | github.com | |
| github.com/dynamics365ninja/d365fo-mcp-server/commit/e70bd051f817ebb652d... | [email protected] | github.com | |
| github.com/dynamics365ninja/d365fo-mcp-server/releases/tag/v1.11.0 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.