Description
A caller-supplied X-Grafana-URL request header controls the destination of mcp-grafana's outbound requests, and the grafana_api_request tool lets the caller also choose the HTTP method, path, and body. Because the destination is not restricted to the configured Grafana instance, a caller can direct requests at internal, loopback, and link-local network services (including metadata endpoints) and read the responses, resulting in server-side request forgery. The fix for CVE-2026-15583 prevented the configured service-account token from being sent to unintended destinations but did not restrict the destinations themselves.
References1
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - EPSS — exploit probability
- 0% percentile: 24 · as of 12 November 2026
- CWE
- CWE-918
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