# CVE-2026-8609: Pre-authentication denial of service via the OAuth login route

> CVE-2026-8609: Pre-authentication denial of service via the OAuth login route. CVSS 5.3 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-8609
Last updated: 2026-10-25T15:10:00Z

- Published: 2026-07-10 14:58 UTC · Updated: 2026-10-25 15:10 UTC · Assigner: GRAFANA
- CVSS: 5.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS: 0.40%, 34th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-400

## Description

An unauthenticated attacker can repeatedly call Grafana's OAuth login route with unique values, causing unbounded memory growth that can eventually exhaust memory and crash the Grafana instance (denial of service).

## Affected vendors and products

- 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-2026-8609)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-8609)
- [https://grafana.com/security/security-advisories/cve-2026-8609](https://grafana.com/security/security-advisories/cve-2026-8609)

---

_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/)_


---
Canonical: https://rewindex.com/cve/CVE-2026-8609 · Markdown: https://rewindex.com/cve/CVE-2026-8609.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-8609 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:10:52.825Z