Quick answers
- Is CVE-2026-123811 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123811 being exploited in the wild.
- How severe is CVE-2026-123811?
- High severity, with a CVSS score of 7.5, published 9 November 2026.
- Which products and versions are affected?
- Dynatrace-Mcp-Server before 2.0.0.
- Is there a fix for CVE-2026-123811?
- Yes: fixed in 2.0.0. Until then: Set the MCP_BEARER_TOKEN environment variable and pass it via the Authorization header with Bearer scheme; default host binding to 127.0.0.1 instead of 0.0.0.0 unless external binding is explicitly required via the --host flag. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123811 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-123811?
- Check whether you run Dynatrace-Mcp-Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 2.0.0
Set the MCP_BEARER_TOKEN environment variable and pass it via the Authorization header with Bearer scheme; default host binding to 127.0.0.1 instead of 0.0.0.0 unless external binding is explicitly required via the --host flag.
Technical details
Prior to version 2.0.0, the HTTP server mode lacked authentication, session validation, and Host/Origin protections on JSON-RPC tool dispatches including execute_dql and create_dynatrace_notebook. An unauthenticated network caller could invoke these methods under the server's configured Dynatrace credentials. The vulnerability was patched by enforcing bearer token authentication with timing-safe comparison and 1 MiB body size limits.
Affected products
- Dynatrace MCP Server before 2.0.0
Timeline
- 2026-11-09: disclosed