CVE-2026-50545 is a critical-severity improper privilege management vulnerability in github.com/fission/fission (go), affecting versions <= 1.23.0. It is fixed in 1.24.0.
Summary A stronger framing of the same root cause as GHSA-gx55-f84r-v3r7: the Environment.spec.runtime.podSpec / spec.builder.podSpec passthrough lacked validation, and MergePodSpec propagated dangerous fields into the generated pods. Details Three independent flaws compounded: Validate gap. pkg/apis/core/v1/validation.go::Environment.Validate checked only container naming conventions, never hostPID/hostIPC/hostNetwork/hostPath/privileged. UPDATE bypass. The pkg/webhook/environment.go kubebuilder marker registered verbs=create only. A tenant could kubectl apply a clean Environment and then kubectl patch in the dangerous fields, the webhook was never called. Merge propagation. pkg/executor/util/merge.go::MergePodSpec unconditionally forwarded HostPID, HostIPC, HostNetwork, Volumes (including hostPath), SecurityContext, and ServiceAccountName into the Deployments generated by poolmgr / newdeploy / buildermgr. A kubectl apply plus a follow-up kubectl patch caused poolmgr to schedule a privileged pod with a host-root mount within roughly 20 seconds. From that pod the cluster CA private key was readable, allowing the attacker to sign arbitrary kubelet certificates and achieve full cluster takeover. Impact environments.fission.io create/update RBAC is escalated to node escape and, via the readable cluster CA key, full cluster takeover. Fix Fixed in #3391 (with the companion buildermgr SA-token fix in #3390) and released in v1.24.0. Each enumerated flaw is addressed: Validate, ValidatePodSpecSafety is called from Environment.Validate for both Runtime.PodSpec and Builder.PodSpec. UPDATE bypass, the webhook marker is extended to verbs=create;update; chart and envtest manifests are aligned. Merge propagation, host namespaces, ServiceAccountName, and hostPath volumes are stripped at the merge layer; per-container privileged/allowPrivilegeEscalation and dangerous capabilities are sanitized. See GHSA-gx55-f84r-v3r7 for the detailed fix, both advisories close to the same commit. Duplicate handling This advisory and GHSA-gx55-f84r-v3r7 were reported separately but close to the same code fix. Both are published to acknowledge each reporter's contribution and to keep the public CVE record clear about the multi-layer nature of the issue.
The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access. Typical impact: privilege escalation beyond the intended level.
CVE-2026-50545 has a CVSS score of 9.9 (Critical). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (1.24.0). Upgrading removes the vulnerable code path.
go
github.com/fission/fission (<= 1.23.0)github.com/fission/fission → 1.24.0 (go)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
Kodem's runtime-powered SCA identifies whether CVE-2026-50545 is reachable in your applications. Explore open-source security for your team.
See if CVE-2026-50545 is reachable in your applications. Get a demo
Already deployed Kodem? See CVE-2026-50545 in your environment →Upgrade github.com/fission/fission to 1.24.0 or later to resolve this vulnerability.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-50545 is a critical-severity improper privilege management vulnerability in github.com/fission/fission (go), affecting versions <= 1.23.0. It is fixed in 1.24.0. The application assigns, modifies, tracks, or checks privileges incorrectly, allowing a user to gain elevated access.
CVE-2026-50545 has a CVSS score of 9.9 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
github.com/fission/fission (go) versions <= 1.23.0 is affected.
Yes. CVE-2026-50545 is fixed in 1.24.0. Upgrade to this version or later.
Whether CVE-2026-50545 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade github.com/fission/fission to 1.24.0 or later.