# CVE-2026-9703: Viewer role can create, modify and delete Loki alerting rules

> CVE-2026-9703: Viewer role can create, modify and delete Loki alerting rules. CVSS 7.1 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-9703
Last updated: 2026-10-16T20:02:37Z

- Published: 2026-10-15 14:02 UTC · Updated: 2026-10-16 20:02 UTC · Assigner: GRAFANA
- CVSS: 7.1 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
- EPSS: 0.19%, 9th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-284

## Description

Grafana's data source proxy did not apply role-based access control to write requests forwarded to Loki data sources. A user holding only the Viewer role on an affected Grafana instance could send POST, PUT and DELETE requests through the proxy to the Loki rules API (/loki/api/v1/rules), allowing them to create, modify and delete Loki alerting rules. Because those rules are stored by Loki rather than by Grafana, the change took effect for every user of that Loki data source, not only for the Viewer who made the request. Exploitation requires an authenticated Viewer account on the Grafana instance and a configured Loki data source; no other privileges are needed. Both Grafana OSS and Grafana Enterprise are affected. The defect is in Grafana's data source proxy; Loki itself is not vulnerable and does not need to be patched.

## Affected vendors and products

- Grafana: Grafana Enterprise
- Grafana: Grafana OSS

## Tracked companies

- [Grafana Cloud](https://rewindex.com/company/grafana-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-9703)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-9703)
- [https://grafana.com/security/security-advisories/cve-2026-9703](https://grafana.com/security/security-advisories/cve-2026-9703)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-9703 · Markdown: https://rewindex.com/cve/CVE-2026-9703.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-9703 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:14:18.589Z