CVE-2026-19516
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.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 15% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 9.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L- Weakness
- CWE-918
- Assigned by
- security@grafana.com
Dates
- Published
- 2026-08-11
- Last modified
- 2026-08-31
- Sources
- NVD