dbcve.org
Flink Kubernetes OperatorApplication · Apache

CVE-2026-40564

MEDIUM · 6.5 CVSS v3.1 Published 2026-05-26
Fix available
A fix is available. Upgrade to 1.15.0 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Files or Directories Accessible to External Parties, Server-Side Request Forgery (SSRF) vulnerability in Apache Flink Kubernetes Operator. The FlinkSessionJob jarURI is currently not validated so that it points to user-owned files or addresses.  This lets a user with CR create permissions read files from the operator pod's filesystem and pull content from any backing store reachable through Flink's pluggable filesystem layer and access them through the submitted Flink job. Furthermore for fetching from http/https addresses there is currently no allowlist on the URI scheme, no host check, no IP-range restriction, and no protection against pointing the URI at internal or link-local addresses.This issue affects Apache Flink Kubernetes Operator: from 1.3.0 before 1.15.0. Users are recommended to upgrade to version 1.15.0, which fixes the issue.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Apache Flink Kubernetes Operator fails to validate the FlinkSessionJob jarURI parameter, allowing users with CR create permissions to read files from the operator pod's filesystem, access any storage reachable via Flink's pluggable filesystem layer, and perform SSRF attacks via http/https URIs without allowlisting, host checking, or IP-range restrictions.

MitigationUpgrade Apache Flink Kubernetes Operator to version 1.15.0 or later; until then, strictly limit CR create permissions and consider network segmentation to reduce exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Flink Kubernetes OperatorApplication
Affected:>= 1.3.0, < 1.15.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Apache Flink Kubernetes Operator version
    Run 'kubectl get deployment -n flink-operator-system' and check the IMAGE TAG, or use 'helm list -n flink-operator-system' to check the chart version, or check the operator pod's container image version
    Affected if The operator version is 1.3.0 through 1.14.x (any version >= 1.3.0 and < 1.15.0)
  2. Verify FlinkSessionJob CRD exists
    Run 'kubectl get crd flinksessionjobs.flink.apache.org' to confirm the Custom Resource Definition is installed
    Affected if The FlinkSessionJob CRD is present in the cluster (indicating the vulnerable feature is available)
  3. List existing FlinkSessionJob resources
    Run 'kubectl get flinksessionjobs -A' to see all FlinkSessionJob instances across namespaces
    Affected if Any FlinkSessionJob resource exists that uses a jarURI parameter pointing to file://, http://, or https:// URIs
  4. Inspect jarURI configuration in FlinkSessionJob resources
    Run 'kubectl get flinksessionjob <name> -n <namespace> -o yaml' and look for the 'jarURI' field under spec.template.spec
    Affected if The jarURI field contains an unvalidated URI (file:// local path, http://, or https:// pointing to internal services or non-allowlisted addresses)
  5. Check RBAC permissions for Custom Resource creation
    Review Kubernetes RBAC bindings: 'kubectl auth can-i create flinksessionjobs' for non-admin users, or inspect RoleBinding/ClusterRoleBinding resources
    Affected if Users or service accounts have permissions to create FlinkSessionJob resources without additional approval

Your environment is affected if the Apache Flink Kubernetes Operator version is 1.3.0 through 1.14.x and FlinkSessionJob resources using jarURI are accessible to users with create permissions.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.15.0 or later
Fixed in 1.15.0
Interim mitigation

Upgrade Apache Flink Kubernetes Operator to version 1.15.0 or later; until then, strictly limit CR create permissions and consider network segmentation to reduce exposure.

Recommended fix High confidence

1.15.0

  1. Review the Apache Flink Kubernetes Operator 1.15.0 release notes and migration guide for any configuration or API changes
  2. Ensure you have a backup of your current FlinkSessionJob and FlinkDeployment custom resources
  3. Update your Helm chart or Kubernetes manifests to reference version 1.15.0 of the Flink Kubernetes Operator
  4. If using Helm, run 'helm upgrade' to apply the new version: helm upgrade <release-name> flink-operator-repo/flink-kubernetes-operator --version 1.15.0
  5. If using kubectl with raw manifests, apply the new 1.15.0 operator YAML files
  6. Verify the operator pods are running correctly: kubectl get pods -n <operator-namespace>
  7. Verify the FlinkSessionJob jarURI validation is working by testing with a non-allowed URI scheme or internal address
  8. Monitor operator logs for any errors during and after the upgrade

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Flink Kubernetes Operator Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-40564 in production — separate from our analysis above.

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What this is

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What belongs here
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