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 p

mediumCVSS 5.3CVE-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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 5.3
Published: 2026-07-23
Last updated: 2026-07-23
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-21723

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-217230.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 10% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-21723	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[NEW] [medium] Grafana: Vulnerability allows denial of servicecert-bund

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 p

Details

Exploitation outlook

Referenced CVEs

Same CVEs, other sources

More from NVD Recent CVEs