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EUVD-2026-360226
European Vulnerability Database identifier assigned by ENISAReserved
2026-10-02 08:30
Assigner
ENISA
Alias of
a CVE record, shown under related vulnerabilities.
This identifier carries no description, severity or references of its own:
they belong to that CVE.
{
"assigner": "ENISA",
"date_reserved": "2026-10-02T08:30:42.258751+00:00",
"id": "EUVD-2026-360226"
}
CVE-2026-21720 (GCVE-0-2026-21720)
Vulnerability from cvelistv5 – Published: 2026-01-27 09:07 – Updated: 2026-08-27 17:22
VLAI
EPSS
VEX
Title
Unauthenticated DoS: avatar cache leaks goroutines when /avatar/:hash requests time out
Summary
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.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-27 14:28 UTC
CWE
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://grafana.com/security/security-advisories/… | vendor-advisory |
| https://access.redhat.com/security/cve/CVE-2026-21720 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2433226 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
Impacted products
15 products
| Vendor | Product | Version | |
|---|---|---|---|
| Grafana | grafana/grafana-enterprise |
Affected:
3.0.0 , < 11.6.9
(semver)
|
|
| Grafana | grafana/grafana-enterprise |
Affected:
3.0.0 , < 12.0.8
(semver)
|
|
| Grafana | grafana/grafana-enterprise |
Affected:
3.0.0 , < 12.1.5
(semver)
|
|
| Grafana | grafana/grafana |
Affected:
3.0.0 , < 11.6.9
(semver)
|
|
| Grafana | grafana/grafana |
Affected:
3.0.0 , < 12.0.8
(semver)
|
|
| Grafana | grafana/grafana |
Affected:
3.0.0 , < 12.1.5
(semver)
|
|
| Grafana | grafana/grafana-enterprise |
Affected:
3.0.0 , < 12.2.3
(semver)
|
|
| Grafana | grafana/grafana |
Affected:
3.0.0 , < 12.2.3
(semver)
|
|
| Grafana | grafana/grafana-enterprise |
Affected:
3.0.0 , < 12.3.1
(semver)
|
|
| Grafana | grafana/grafana |
Affected:
3.0.0 , < 12.3.1
(semver)
|
|
| Red Hat | Red Hat Ceph Storage 7 |
cpe:/a:redhat:ceph_storage:7
|
|
| Red Hat | Red Hat Ceph Storage 8 |
cpe:/a:redhat:ceph_storage:8
|
|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10
|
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9
|
Date Public
2026-01-27 09:03
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Trend slope:
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(linear fit over daily sighting counts)
Show additional events:
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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