CVE-2026-114123 dynamics365ninja CVE debrief

Who should care

Defenders responsible for D365 F&O MCP Server deployments, especially those using the official Azure one-click deployment, should assess exposure and prioritize securing their environments to prevent unauthorized access to proprietary X++ source code and metadata.

Why it matters

CVE-2026-114123 is a high-severity vulnerability in D365 F&O MCP Server's official Azure one-click deployment, allowing unauthenticated access to proprietary X++ source code and metadata. Defenders should prioritize verifying and securing deployments to prevent unauthorized access.

• Verify and secure D365 F&O MCP Server deployments to prevent unauthorized access.
• Assess exposure and prioritize patching or mitigation for affected deployments.
• Monitor for potential unauthorized access to proprietary X++ source code and metadata.
• Implement compensating controls, such as network restrictions or upstream authentication, to prevent exploitation.

Technical summary

The D365 F&O MCP Server's official Azure one-click deployment uses an empty API key by default, allowing unauthenticated access to proprietary X++ source code and metadata. The vulnerability affects versions prior to 1.11.0. The deployment's MCP_SERVER_MODE=read-only setting does not prevent anonymous access to read/search tools. Exposed information can include business logic, extension and event-handler wiring, security-role and privilege structure, and labels. Defenders should prioritize verifying and securing D365 F&O MCP Server deployments to prevent unauthorized access.

Defensive priority

Defenders should prioritize verifying and securing D365 F&O MCP Server deployments, especially those using the official Azure one-click deployment, to prevent unauthorized access to proprietary X++ source code and metadata.

Recommended defensive actions

• Verify D365 F&O MCP Server deployments, especially those using the official Azure one-click deployment, to ensure authentication is enabled.
• Check for and apply the patch to update the deployment configuration to use a non-empty API key.
• Implement separate network restrictions or upstream authentication to prevent unauthorized access.
• Monitor for and respond to potential unauthorized access to proprietary X++ source code and metadata.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and source item provide details on the vulnerability, including the affected version and deployment configuration. However, the corpus does not provide information on actual exploitation or victim impact.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.