Grafana up to 12.3.2 Alertmanager Templates Test Endpoint test resource consumption

Summaryinfo

A vulnerability classified as problematic has been found in Grafana up to 12.3.2. The affected element is an unknown function of the file /api/alertmanager/grafana/config/api/v1/templates/test of the component Alertmanager Templates Test Endpoint. This manipulation causes resource consumption. This vulnerability is registered as CVE-2026-21723. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as problematic was found in Grafana up to 12.3.2. Affected by this vulnerability is some unknown processing of the file /api/alertmanager/grafana/config/api/v1/templates/test of the component Alertmanager Templates Test Endpoint. The manipulation with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at grafana.com. This vulnerability is known as CVE-2026-21723 since 01/05/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-47869). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Grafana

Version

• 11.0
• 11.6.0
• 11.6.1
• 11.6.2
• 11.6.3
• 11.6.4
• 11.6.5
• 11.6.6
• 11.6.7
• 11.6.8
• 11.6.9
• 11.6.10
• 12.0.0
• 12.0.1
• 12.0.2
• 12.0.3
• 12.0.4
• 12.0.5
• 12.0.6
• 12.0.7
• 12.0.8
• 12.0.9
• 12.1.0
• 12.1.1
• 12.1.2
• 12.1.3
• 12.1.4
• 12.1.5
• 12.1.6
• 12.2.0
• 12.2.1
• 12.2.2
• 12.2.3
• 12.2.4
• 12.3.0
• 12.3.1
• 12.3.2

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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CVSSv2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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