CVE-2026-63087

CRITICAL 9.8

Grafana OnCall 1.16.11 Unauthenticated Token Hijack via Plugin Install Endpoint

CVSS Score

9.8

EPSS Score

0.0%

EPSS Percentile

0th

Grafana OnCall through 1.16.11 contains an unauthenticated access vulnerability that allows remote attackers to obtain a valid PluginAuthToken by sending a POST request to the internal plugin install endpoint using hardcoded default stack_id and org_id values present in the public source tree. Attackers can leverage the acquired token to authenticate against all internal API endpoints, create arbitrary Admin users via the user-context header bootstrap path, revoke the legitimate plugin token, and redirect OnCall-to-Grafana API calls to an attacker-controlled host by overwriting the organization's grafana_url and api_token.

CWE	CWE-306
Vendor	grafana-cold-storage
Product	oncall
Published	Jul 16, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Affected Versions

grafana-cold-storage / oncall

0 ≤ 1.16.11

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/geo-chen/oss/blob/main/oncall.md vulncheck.com: https://www.vulncheck.com/advisories/grafana-oncall-unauthenticated-token-hijack-via-plugin-install-endpoint

Credits

George Chen