GHSA-wmgg-3p4h-48x7 is a critical-severity (CVSS 9.9) Improper Privilege Management vulnerability in github.com/fission/fission. A fix is available for github.com/fission/fission — see the affected versions and patch details below.
Fission Environment CRD PodSpec Injection Leading to Node Escape and Cluster Takeover
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-wmgg-3p4h-48x7.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-wmgg-3p4h-48x7 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 380,066 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/fission/fissionReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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.Validatechecked only container naming conventions, neverhostPID/hostIPC/hostNetwork/hostPath/privileged. - UPDATE bypass. The
pkg/webhook/environment.gokubebuilder marker registeredverbs=createonly. A tenant couldkubectl applya clean Environment and thenkubectl patchin the dangerous fields — the webhook was never called. - Merge propagation.
pkg/executor/util/merge.go::MergePodSpecunconditionally forwardedHostPID,HostIPC,HostNetwork,Volumes(including hostPath),SecurityContext, andServiceAccountNameinto 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 —
ValidatePodSpecSafetyis called fromEnvironment.Validatefor bothRuntime.PodSpecandBuilder.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-containerprivileged/allowPrivilegeEscalationand 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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/fission/fission | all versions | 1.24.0go get github.com/fission/fission@v1.24.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/fission/fission, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/fission/fission to 1.24.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wmgg-3p4h-48x7 is resolved across your whole dependency graph.
Workarounds
Close the privilege gap rather than the entry point: audit which accounts, roles and service identities can reach the affected operation, drop the component to the least privilege it actually needs, and review file and directory permissions created by earlier installs — a default left in place is what makes this reachable.
Frequently Asked Questions
Is GHSA-wmgg-3p4h-48x7 in your dependencies?
Find it across Go, including transitive dependencies.