CVE & CISA-KEV Catalog

CVE-2026-21720

HIGH
7.5
CVSS v3
NVD

Description

Every uncached /avatar/:hash request spawns a goroutine that refreshes the Gravatar image. If the refresh sits in the 10-slot worker queue longer than three seconds, the handler times out and stops listening for the result, so that goroutine blocks forever trying to send on an unbuffered channel. Sustained traffic with random hashes keeps tripping this timeout, so goroutine count grows linearly, eventually exhausting memory and causing Grafana to crash on some systems.

CWE-400Resource ExhaustionCWE-703CWE-772

How to fix

Remediation Available
GrafanaEnterpriseWindows application
Affected:3.0.0 11.6.9Fixed in:11.6.9Grafana Labs
Affected:12.1.0 12.1.5Fixed in:12.1.5Grafana Labs
Affected:12.2.0 12.2.3Fixed in:12.2.3Grafana Labs
Affected:12.0.0 12.0.8Fixed in:12.0.8Grafana Labs
GrafanaOSSWindows application
Affected:3.0.0 11.6.9Fixed in:11.6.9Grafana Labs
Affected:12.2.0 12.2.3Fixed in:12.2.3Grafana Labs
Affected:12.1.0 12.1.5Fixed in:12.1.5Grafana Labs
Affected:12.0.0 12.0.8Fixed in:12.0.8Grafana Labs

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Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

0.62%probability of exploitation in 30 days
46thpercentile

Moderate risk: more likely to be exploited than 46% of all known CVEs.

References

Related Vulnerabilities

Other CWE-400 (Resource Exhaustion) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2023-44487High7.5100%KEVFix
CVE-2021-44228Critical10.0100%KEV + RansomFix
CVE-2011-3192High7.899%-Fix
CVE-2019-11478Medium5.395%-Fix
CVE-2024-25617Medium5.389%-Fix
CVE-2018-1000115High7.588%-Fix
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-07-15.