# CVE-2026-123811: Dynatrace MCP Server: Unauthenticated HTTP MCP Tool Invocation in `@dynatrace-oss/dynatrace-mcp-server`


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 9 Nov 2026
- **Updated:** 9 Nov 2026
- **Also known as:** GHSA-p7w7-4929-vpj5

## What is CVE-2026-123811?

CVE-2026-123811 is a high-severity vulnerability in dynatrace-oss dynatrace-mcp, published on 9 Nov 2026. 

### Official description

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.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2026-123811?

1 open source package ship an affected version, including @dynatrace-oss/dynatrace-mcp-server.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@dynatrace-oss/dynatrace-mcp-server` | npm | All versions | 2.0.0 |

## How do I fix CVE-2026-123811?

Upgrade @dynatrace-oss/dynatrace-mcp-server to 2.0.0 or later.

## Is CVE-2026-123811 being exploited?

There is no known exploitation of CVE-2026-123811 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-123811 and fix it if it is affected.

What it is: CVE-2026-123811 is a high-severity vulnerability in dynatrace-oss dynatrace-mcp, published on 9 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-123811 in the wild and no public exploit code.

Affected packages and fixed versions:
- @dynatrace-oss/dynatrace-mcp-server (npm): affected all versions; fixed in 2.0.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-123811/ (Markdown: https://insights.sbomify.com/CVE-2026-123811/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-123811
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-123811
- OSV: https://osv.dev/vulnerability/CVE-2026-123811

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-123811/
Summaries are generated and may contain mistakes; the official description above is the record.