CVE-2026-21723

The alertmanager templates test endpoint (/api/alertmanager/grafana/config/api/v1/templates/test) can execute templates with no memory limits. Mass-executing templates in a short period causes OOM and crashes the Grafana service. The endpoint requires very low privileges and is exploitable with anonymous access enabled.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://grafana.com/security/security-advisories/cve-2026-21723

Configurations

No configuration.

History

23 Jul 2026, 15:17

Type	Values Removed	Values Added
CWE		CWE-400

23 Jul 2026, 03:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-23 03:16

Updated : 2026-07-23 17:55

NVD link : CVE-2026-21723

Mitre link : CVE-2026-21723

CVE.ORG link : CVE-2026-21723

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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