CVE-2026-50563 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 Fission's Container Executor path lets a tenant supply Function.spec.podspec directly; the executor merges it into the executor-built podspec and creates a Deployment whose pods run the user's container image. Details Two flaws compounded: pkg/apis/core/v1/validation.go::FunctionSpec.Validate only checked that spec.PodSpec != nil when executorType: container; it did not inspect the content of spec.PodSpec. pkg/executor/util/merge.go::MergePodSpec unconditionally forwarded hostPID, hostNetwork, hostIPC, hostPath volumes, serviceAccountName, and container privileged into the Deployment spec via the container-executor sink (pkg/executor/executortype/container/deployment.go::getDeploymentSpec). A tenant with only functions.fission.io/create could deploy a Function with a crafted podspec that mounted the host root filesystem and shared host namespaces. The executor, running under its high-privilege SA, which holds deployments/create on the function namespace, created that Deployment on the tenant's behalf, turning Function-create into effective deployments/create with arbitrary pod-security configuration. This is the Function-CRD sibling of GHSA-gx55-f84r-v3r7 / GHSA-wmgg-3p4h-48x7, with a lower attack threshold: regular function developers typically hold functions/create but not environments/create. Impact A tenant with only functions.fission.io/create is escalated to node escape via a privileged, host-namespace pod scheduled by the executor. Fix Fixed in #3391 and released in v1.24.0. FunctionSpec.Validate now calls ValidatePodSpecSafety("Function.spec.podspec", spec.PodSpec) after the existing spec.PodSpec == nil check. The Function validating webhook is already registered on verbs=create;update, so it picks up the new validation with no marker change. The same merge-layer strip and per-container sanitize used for the Environment path applies here, since the container-executor sink calls util.MergePodSpec. See GHSA-gx55-f84r-v3r7 for the detailed fix. Behavioural change Functions whose spec.podspec sets host namespaces, hostPath volumes, container privileged/allowPrivilegeEscalation, dangerous Linux capabilities, or a serviceAccountName override are now rejected at admission. Legitimate container-executor functions that set image, command, args, env, resources, nodeSelector, tolerations, affinity, non-hostPath volumes, or volumeMounts are unaffected.
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-2026-50563 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-2026-50563 is reachable in your applications. Explore open-source security for your team.
See if CVE-2026-50563 is reachable in your applications. Get a demo
Already deployed Kodem? See CVE-2026-50563 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-2026-50563 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-2026-50563 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-2026-50563 is fixed in 1.24.0. Upgrade to this version or later.
Whether CVE-2026-50563 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.