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CVE-2026-50565 Fission CVE debrief

A vulnerability was found in Fission, an open-source, Kubernetes-native serverless framework. Prior to version 1.24.0, Fission builder pods were created with ServiceAccountName: fission-builder and no AutomountServiceAccountToken: false. This configuration allowed the kubelet to auto-mount the service-account token into every container in the pod, including the user-supplied builder image. The issue has been patched in version 1.24.0.

Vendor
Fission
Product
Fission
CVSS
MEDIUM 4.9
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-10
Original CVE updated
2026-06-10
Advisory published
2026-06-10
Advisory updated
2026-06-10

Who should care

Users of Fission versions prior to 1.24.0 who deploy functions and applications on Kubernetes using the Fission framework.

Technical summary

Fission builder pods were created with ServiceAccountName: fission-builder and no AutomountServiceAccountToken: false. This allowed the kubelet to auto-mount the service-account token into every container in the pod, including the user-supplied builder image.

Defensive priority

MEDIUM

Recommended defensive actions

  • Upgrade to Fission version 1.24.0 or later.
  • Review and update existing Fission deployments to ensure AutomountServiceAccountToken: false is set for builder pods.

Evidence notes

The vulnerability was patched in version 1.24.0. References: [ref-5](https://github.com/fission/fission/releases/tag/v1.24.0), [ref-4](https://github.com/fission/fission/pull/3390), [ref-6](https://github.com/fission/fission/security/advisories/GHSA-8wcj-mfrc-jx5q).

Official resources

CVE-2026-50565 was published on [cvePublishedAt].