PatchSiren cyber security CVE debrief
CVE-2026-50564 Fission CVE debrief
CVE-2026-50564 is a critical security vulnerability in Fission, an open-source, Kubernetes-native serverless framework. The issue allows for potential privilege escalation due to the Environment CRD exposing spec.runtime.podSpec and spec.builder.podSpec, which are merged into Kubernetes pod specs without adequate filtering or validation. This could enable an attacker to exploit the system by setting hostNetwork, hostPID, hostIPC, container privileged, and serviceAccountName fields. The vulnerability has been patched in version 1.24.0.
- Vendor
- Fission
- Product
- Fission
- CVSS
- CRITICAL 9.9
- 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, especially those who have not upgraded to version 1.24.0, should be aware of this vulnerability and take immediate action to mitigate potential risks.
Technical summary
The Environment CRD in Fission exposes spec.runtime.podSpec and spec.builder.podSpec, which are merged into Kubernetes pod specs for runtime and builder pods. Prior to version 1.24.0, the merge logic propagated sensitive fields such as hostNetwork, hostPID, hostIPC, container privileged, and serviceAccountName without filtering. Environment.Validate did not perform security-relevant checks on these fields, potentially allowing an attacker to escalate privileges.
Defensive priority
High
Recommended defensive actions
- Upgrade to Fission version 1.24.0 or later to apply the patch.
- Review and restrict user-supplied pod specs to prevent exploitation of sensitive fields.
- Implement additional security measures, such as network policies and role-based access control, to limit potential damage.
Evidence notes
The CVE-2026-50564 issue has a CVSS score of 9.9 and is classified as CRITICAL. The vulnerability was published on 2026-06-10T18:17:12.740Z and modified on 2026-06-10T19:37:41.437Z.
Official resources
CVE-2026-50564 was published on 2026-06-10T18:17:12.740Z and modified on 2026-06-10T19:37:41.437Z.