ECK Secret Leakage via Unvalidated Namespace Annotation (CVE-2026-72640)
CVE-2026-72640 Published on August 13, 2026

Unintended Proxy or Intermediary in Elastic Cloud on Kubernetes Leading to Cross-Namespace Secret Disclosure
The Elastic Cloud on Kubernetes (ECK) operator reads a list of secret references from an annotation on secrets it manages, and it accepts the namespace recorded in each reference without validating that the reference is authorized for the resource being reconciled. A user whose Kubernetes permissions are limited to their own namespace can write that annotation, trigger a reconcile, and cause the operator to use its cluster-wide secret permissions to copy the contents of a secret from any other namespace into a secret the user can read.

NVD

Vulnerability Analysis

CVE-2026-72640 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity and availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
LOW
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
NONE
Availability Impact:
NONE

Weakness Type

What is a Confused Deputy Vulnerability?

The product receives a request, message, or directive from an upstream component, but the product does not sufficiently preserve the original source of the request before forwarding the request to an external actor that is outside of the product's control sphere. This causes the product to appear to be the source of the request, leading it to act as a proxy or other intermediary between the upstream component and the external actor.

CVE-2026-72640 has been classified to as a Confused Deputy vulnerability or weakness.


Affected Versions

Elastic Eck Operator: