CVE-2026-21723
MEDIUMGrafana OSS Alertmanager Templates Test Endpoint - Denial of Service
Title source: manualDescription
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.
References (1)
Core 1
Core References
Vendor Advisory vendor-advisory
https://grafana.com/security/security-advisories/cve-2026-21723
Scores
CVSS v3
5.3
EPSS
0.0020
EPSS Percentile
9.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-400
Status
published
Products (6)
Grafana/Grafana OSS
11.0.0 - 11.6.10
Grafana/Grafana OSS
12.0.0 - 12.0.9
Grafana/Grafana OSS
12.1.0 - 12.1.6
Grafana/Grafana OSS
12.2.0 - 12.2.4
Grafana/Grafana OSS
12.3.0 - 12.3.2
Grafana/Grafana OSS
8.0.0 - 11.0.0
Published
Jul 23, 2026
Tracked Since
Jul 23, 2026