CVE-2026-42875Network attack vector

Cross-namespace ConfigMap existence disclosure via unchecked CA resolution

Published May 11, 2026 · Updated May 11, 2026

Improper authorization in External Secrets Operator before 2.4.0 allows remote authenticated users to infer cross-namespace ConfigMap key existence. The shared runtime CA resolver honors caProvider.namespace for ConfigMap references without enforcing the SecretStore namespace boundary. Kubernetes permission to create or modify a namespaced SecretStore is required; CA data is consumed as trust material rather than returned directly.

CVSS severity5.3
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in External Secrets Operator before 2.4.0 allows remote authenticated users to infer cross-namespace ConfigMap key existence. The shared runtime CA resolver honors caProvider.namespace for ConfigMap references without enforcing the SecretStore namespace boundary. Kubernetes permission to create or modify a namespaced SecretStore is required; CA data is consumed as trust material rather than returned directly.

The record

CVE
CVE-2026-42875
Published
May 11, 2026
Updated
May 11, 2026
Vendor
External Secrets
Product
External Secrets Operator
Classifications
CWE-668, CWE-285, T1613
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 11, 2026CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

External Secrets · External Secrets Operatorversion=< 2.4.0

Published CVSS scores

5.3GitHub, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-668Exposure of Resource to Wrong Sphere
CWE-285Improper Authorization
T1613Container and Resource Discovery

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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