D365 F&O MCP Server: Official Azure one-click deployment ships with authentication disabled by default, exposing proprietary X++ source over the public internet
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.
CVE-2026-114123
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-114123
d365fo-mcp-server
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "dynamics365ninja",
"product": "d365fo-mcp-server",
"versions": [
{
"status": "affected",
"version": "< 1.11.0"
}
]
}
]- Related CVEs
- CVE-2026-114123
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #49289 · Revision 1
- Added to Heist Feed
- Publisher date