Auth bypass in Dynatrace-Oss Dynatrace-Mcp

CVE-2026-123811

Dynatrace MCP Server is an MCP server for Dynatrace Observability. Prior to 2.0.0, a server started with the --http option accepts JSON-RPC tools/call requests without authentication, session validation, or Host and Origin protections before dispatching them under the server's configured Dynatrace credentials. A network-reachable caller can invoke execute_dql to read logs, security events, user sessions, and other Grail data, or invoke create_dynatrace_notebook to create tenant-visible notebooks. The send_event path is not affected because its requestHumanApproval gate blocks this attack path, and reset_grail_budget only demonstrates dispatch without accessing Dynatrace data. This issue is fixed in version 2.0.0.

Vulnerability class: Broken Authentication

Published .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-123811?
CVE-2026-123811 is a high-severity vulnerability in Dynatrace-Oss Dynatrace-Mcp, classified under Missing Authentication for Critical Function. CVSS score: 7.5/10. Published 2026-11-09.
How severe is CVE-2026-123811?
High severity. CVSS v3 base score is 7.5 out of 10.