CVE-2026-21729: Vulnerability in Grafana Loki
CVE-2026-21729 is a high-severity vulnerability in Grafana Loki version 3.0.0 where queries with large limits can cause excessive memory allocations. This behavior can impact the availability of the Loki service depending on how it is deployed, potentially leading to denial of service conditions.
AI Analysis
Technical Summary
This vulnerability in Grafana Loki 3.0.0 arises from the handling of queries that specify large limits, which can trigger large memory allocations. Such allocations may exhaust system resources and degrade or disrupt service availability. The CVSS 3.1 score is 7.5, reflecting a network attack vector with no privileges or user interaction required, and the impact is limited to availability without confidentiality or integrity loss. No official patch or remediation level has been published at this time, and no known exploits are reported in the wild.
Potential Impact
The primary impact is on availability, as large memory allocations caused by crafted Loki queries can degrade or interrupt the service. There is no impact on confidentiality or integrity according to the CVSS vector. The severity is high due to the potential for denial of service.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider limiting query limits or applying resource constraints on Loki deployments to mitigate potential memory exhaustion. Monitor vendor communications for updates on patches or official mitigations.
CVE-2026-21729: Vulnerability in Grafana Loki
Description
CVE-2026-21729 is a high-severity vulnerability in Grafana Loki version 3.0.0 where queries with large limits can cause excessive memory allocations. This behavior can impact the availability of the Loki service depending on how it is deployed, potentially leading to denial of service conditions.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Grafana Loki 3.0.0 arises from the handling of queries that specify large limits, which can trigger large memory allocations. Such allocations may exhaust system resources and degrade or disrupt service availability. The CVSS 3.1 score is 7.5, reflecting a network attack vector with no privileges or user interaction required, and the impact is limited to availability without confidentiality or integrity loss. No official patch or remediation level has been published at this time, and no known exploits are reported in the wild.
Potential Impact
The primary impact is on availability, as large memory allocations caused by crafted Loki queries can degrade or interrupt the service. There is no impact on confidentiality or integrity according to the CVSS vector. The severity is high due to the potential for denial of service.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider limiting query limits or applying resource constraints on Loki deployments to mitigate potential memory exhaustion. Monitor vendor communications for updates on patches or official mitigations.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GRAFANA
- Date Reserved
- 2026-01-05T09:26:06.215Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a588e6368715ace439dd829
Added to database: 07/16/2026, 07:55:15 UTC
Last enriched: 07/16/2026, 08:02:29 UTC
Last updated: 07/16/2026, 08:38:50 UTC
Views: 8
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