Privilege escalation in Fission
CVE-2026-50564
Fission is an open-source, Kubernetes-native serverless framework that simplifies the deployment of functions and applications on Kubernetes. Prior to version 1.24.0, Fission's Environment CRD exposes spec.runtime.podSpec and spec.builder.podSpec, which are merged into the Kubernetes pod specs for runtime and builder pods. The merge logic propagated hostNetwork, hostPID, hostIPC, container privileged, and serviceAccountName from the user-supplied podspec with no filtering, and Environment.Validate performed no security-relevant checks on these fields. This issue has been patched in version 1.24.0.
Vulnerability class: Privilege Escalation
EPSS: 0.003 (19.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Fission — versions < 1.24.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_CONFIRM)
Frequently asked questions
- What is CVE-2026-50564?
- CVE-2026-50564 is a critical-severity vulnerability in Fission, classified under Improper Privilege Management. CVSS score: 9.9/10. Published 2026-06-10.
- How severe is CVE-2026-50564?
- Critical severity. CVSS v3 base score is 9.9 out of 10.