CVE-2026-21723Network attack vector

Service crash via unbounded template execution

Published Jul 23, 2026 · Updated Jul 23, 2026

Uncontrolled resource consumption in Grafana OSS 8.0.0 through 12.3.2 allows remote authenticated users to crash the service. The Alertmanager templates test endpoint executes supplied templates without memory limits, so rapid mass execution exhausts process memory and triggers an out-of-memory crash. Low-privileged access reaches the endpoint, and instances with anonymous access enabled expose the same service-interruption path without authentication.

CVSS severity5.3
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in Grafana OSS 8.0.0 through 12.3.2 allows remote authenticated users to crash the service. The Alertmanager templates test endpoint executes supplied templates without memory limits, so rapid mass execution exhausts process memory and triggers an out-of-memory crash. Low-privileged access reaches the endpoint, and instances with anonymous access enabled expose the same service-interruption path without authentication.

The record

CVE
CVE-2026-21723
Published
Jul 23, 2026
Updated
Jul 23, 2026
Vendor
Grafana Labs
Product
Grafana OSS
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=11.0.0 <=11.6.10
  2. Affected versionversion=12.0.0 <=12.0.9
  3. Affected versionversion=12.1.0 <=12.1.6
  4. Affected versionversion=12.2.0 <=12.2.4
  5. Affected versionversion=12.3.0 <=12.3.2
  6. Affected versionversion=8.0.0 <=11.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Grafana Labs · Grafana OSSversion=11.0.0 <=11.6.10; version=12.0.0 <=12.0.9; version=12.1.0 <=12.1.6; version=12.2.0 <=12.2.4; version=12.3.0 <=12.3.2; version=8.0.0 <=11.0.0

Published CVSS scores

5.3Grafana LabsCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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