CVE-2026-42127
Description
A flaw was found in Grafana. An unauthenticated attacker can exploit the public dashboard query endpoint by sending arbitrarily large JSON payloads. This vulnerability, caused by a lack of request body size limits, triggers excessive memory allocation, leading to a denial of service through memory exhaustion.
Statement
This is an Important denial of service vulnerability in Grafana, affecting Red Hat products that include Grafana. Unauthenticated remote attackers can exploit the public dashboard query endpoint by sending large JSON payloads, leading to excessive memory allocation and potential service disruption. The absence of authentication requirements for exploitation increases the risk of widespread impact.
Mitigation
Restrict network access to the Grafana instance to only trusted clients and networks. This can be achieved by configuring firewall rules to limit inbound connections to the Grafana service port. If Grafana is exposed via a reverse proxy, ensure the proxy is configured to limit request body sizes to prevent large payloads from reaching Grafana. A service restart may be required for network configuration changes to take effect.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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