CVE-2026-42875 MEDIUM

CVE-2026-42875: External Secrets Operator: Namespace Isolation Bypass in CAProvider ConfigMap Resolution for SecretStore

Vendor External-Secrets
Product external-secrets
Weakness CWE-285
Published May 11, 2026
Last update May 12, 2026

CVSS base score

5.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality
Integrity

CVSS vector

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

What the vulnerability does

01Description

External Secrets Operator reads information from a third-party service and automatically injects the values as Kubernetes Secrets. Prior to 2.4.0, Namespaced SecretStore resources that used CAProvider with type ConfigMap could resolve CA material from another namespace when caProvider.namespace was set. This bypassed the namespace boundary enforced for SecretStore-backed references in providers that rely on the shared runtime CA resolver. This vulnerability is fixed in 2.4.0.

Key dates

02Disclosure timeline

May 11, 2026 CVE published
May 12, 2026 Record updated