High severity · published Jul 16, 2026
CVE-2026-21729
Loki detected_fields query limits results in unbounded memory allocation
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
Loki queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
Grafana · Grafana
v3.0.0 before v3.7.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21729
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21729
grafana.com
https://grafana.com/security/security-advisories/cve-2026-21729
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