What is the CVSS score of EUVD-2026-58286?

EUVD-2026-58286 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N. EPSS exploitation probability: 0.2%.

ECK Operator EUVD-2026-58286

| CVE-2026-72640 MEDIUM

Unintended Proxy or Intermediary ('Confused Deputy') (CWE-441)

2026-08-13 elastic

GHSA-vvr2-6gx7-cxv9

Information Disclosure Kubernetes Elastic Eck Operator

6.5

CVSS 3.1 · Vendor: elastic

Severity by source

Vendor (elastic) PRIMARY

6.5 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

vuln.today AI

7.7 HIGH

Scope changed to S:C because the attack crosses Kubernetes namespace authorization boundaries to impact secrets the attacker has no RBAC access to; PR:L reflects the required authenticated namespace-level write access.

3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N

Primary rating from Vendor (elastic).

CVSS VectorVendor: elastic

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

Aug 13, 2026 - 20:15 vuln.today

DescriptionCVE.org

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.

AnalysisAI

Cross-namespace secret exfiltration in the Elastic Cloud on Kubernetes (ECK) operator allows any low-privileged Kubernetes tenant to read secrets from arbitrary namespaces cluster-wide. The operator's reconciliation loop blindly trusts namespace references embedded in secret annotations without verifying whether the requesting user is authorized to access the referenced namespace, enabling a classic confused-deputy (CWE-441) privilege escalation that breaks Kubernetes RBAC namespace isolation. No public exploit code has been identified at time of analysis, but the low attack complexity and high confidentiality impact make this a material priority for any multi-tenant Kubernetes deployment running ECK; vendor-released patch version 3.5.0 is available per ESA-2026-121.

Technical ContextAI

The ECK operator (CPE: cpe:2.3:a:elastic:eck_operator:*:*:*:*:*:*:*:*) manages Elastic Stack components - Elasticsearch, Kibana, APM Server, and related resources - within Kubernetes clusters and requires cluster-scoped RBAC permissions to do so, including the ability to read secrets across all namespaces. As part of its reconciliation logic, the operator reads a list of secret references encoded in annotations on secrets it manages; these references may specify secrets in arbitrary namespaces. CWE-441 (Unintended Proxy or Intermediary, the 'confused deputy' problem) applies precisely here: the operator acts on those cross-namespace references using its own elevated cluster-wide credentials, without validating whether the Kubernetes principal who wrote the annotation holds any authorization over the referenced namespace. This bypasses the Kubernetes RBAC namespace isolation model entirely, as the operator becomes an unwitting proxy that launders a low-privileged user's request into a privileged cross-namespace secret read.

RemediationAI

Upgrade the ECK operator to version 3.5.0 or later as detailed in ESA-2026-121 at https://discuss.elastic.co/t/elastic-cloud-on-kubernetes-3-5-0-security-update-esa-2026-121/389494; this is the primary and preferred remediation. If immediate upgrade is not feasible, deploy a Kubernetes admission webhook or OPA/Gatekeeper policy to reject or strip the ECK cross-namespace secret reference annotation on secrets created or modified by unprivileged namespace users - note this may interfere with legitimate ECK workflows and must be tested against your Elastic Stack topology before production rollout. As a detection-oriented compensating control, audit existing ECK-managed secret annotations for cross-namespace references pointing to namespaces the annotating user does not own, which may indicate prior exploitation. No additional workaround short of blocking the annotation path meaningfully reduces exposure given how central the reconciliation annotation is to the operator's design.