CVE-2026-50570: fission Improper Privilege Management

Vulnerability summary

CVE-2026-50570 is a high (CVSS 8.5) Improper Privilege Management vulnerability in fission. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 39% of scored vulnerabilities.

Timeline

1. 10-06-2026
   PublishedVulnerability first disclosed.
2. 10-06-2026
   Last modifiedVulnerability information updated.

Description

Fission is an open-source, Kubernetes-native serverless framework that simplifies the deployment of functions and applications on Kubernetes. Prior to version 1.25.0, Fission added PodSpec safety validation for tenant-facing Environment and Function CRDs (ValidatePodSpecSafety / ValidateContainerSafety admission webhook + sanitizeContainerSecurityContext executor merge layer), but the capability check was implemented as a fixed denylist of six Linux capabilities (SYS_ADMIN, NET_ADMIN, SYS_PTRACE, SYS_MODULE, DAC_READ_SEARCH, DAC_OVERRIDE). The denylist omitted CAP_SYS_TIME, among others. As a result, a tenant who could create a Function or Environment CRD could request securityContext.capabilities.add: ["SYS_TIME"], pass Fission's admission validation and merge-layer sanitization, and run attacker-controlled code with CAP_SYS_TIME in the resulting function or runtime container. This issue has been patched in version 1.25.0.

• CWE-269Improper Privilege ManagementThe product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
• CWE-732Incorrect Permission Assignment for Critical ResourceThe product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.