CVE-2026-33413
Description
A flaw was found in etcd, a distributed key-value store. Unauthorized users can bypass authentication or authorization checks when the gRPC API is exposed to untrusted clients. This allows them to access sensitive cluster topology information, disrupt operations through alarms, interfere with lease management, and trigger data compaction, leading to permanent data loss and disruption of critical workflows. This vulnerability can result in information disclosure and denial of service.
Statement
This flaw in etcd allows unauthorized users to bypass authentication or authorization checks when the gRPC API is exposed to untrusted clients and etcd's built-in authentication is enabled. This can lead to information disclosure and denial of service. Typical Red Hat OpenShift Container Platform and Kubernetes deployments are not affected, as the Kubernetes API server handles authentication and authorization independently of etcd's internal mechanisms.
Mitigation
Restrict network access to etcd server ports to ensure only trusted components can establish connections. Implement strong client identity at the transport layer, such as mTLS, with tightly scoped client certificate distribution. This will limit unauthorized access to etcd functions.
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 | 7.7 | 8.8 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | None | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | Low | High | N/A |
| Integrity Impact | High | High | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Access Control,Other
Technical Impact: Gain Privileges or Assume Identity; Varies by Context
Exposing critical functionality essentially provides an attacker with the privilege level of that functionality. The consequences will depend on the associated functionality, but they can range from reading or modifying sensitive data, accessing administrative or other privileged functionality, or possibly even executing arbitrary code.
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