PatchSiren cyber security CVE debrief
CVE-2026-50566 fission CVE debrief
CVE-2026-50566 is a critical vulnerability in Fission, a Kubernetes-native serverless framework. Prior to version 1.24.0, a tenant with environments.fission.io create/update RBAC can run privileged / allowPrivilegeEscalation / dangerous-capability containers in the Fission function or builder namespace, scheduled under the executor's high-privilege service account. This enables container-sandbox escape, host filesystem and network access, and potential node- and cluster-level compromise.
- Vendor
- fission
- Product
- Unknown
- CVSS
- CRITICAL 9.9
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-06-10
- Original CVE updated
- 2026-06-12
- Advisory published
- 2026-06-10
- Advisory updated
- 2026-06-12
Who should care
Users of Fission, a Kubernetes-native serverless framework, should be aware of this critical vulnerability. Specifically, tenants with environments.fission.io create/update RBAC are at risk.
Technical summary
The vulnerability has a CVSS score of 9.9 and is classified as CRITICAL. It was published on [cvePublishedAt] and modified on [cveModifiedAt]. The vulnerability is associated with CWE-250 and CWE-269.
Defensive priority
HIGH
Recommended defensive actions
- Upgrade to Fission version 1.24.0 or later.
- Review and restrict environments.fission.io create/update RBAC permissions.
- Monitor Fission function and builder namespaces for suspicious activity.
Evidence notes
Evidence for this CVE can be found at [resourceLinkAnnotations].
Sources and references
Verified primary and authoritative sources
-
CVE-2026-50566 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-50566
CVE Program - Official CVE Program record with source-provided CVE metadata.
-
CVE-2026-50566 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-50566
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
-
Source reference
Unverified legacy reference
URL: https://github.com/fission/fission/pull/3406
-
Source reference
Unverified legacy reference
URL: https://github.com/fission/fission/releases/tag/v1.24.0
-
Source reference
Unverified legacy reference
URL: https://github.com/fission/fission/security/advisories/GHSA-m63v-2g9w-2w6v
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.