GHSA-v455-mv2v-5g92 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 Container Executor Function PodSpec Injection Leading to Node Escape
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-v455-mv2v-5g92.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-v455-mv2v-5g92 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
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.Validateonly checked thatspec.PodSpec != nilwhenexecutorType: container; it did not inspect the content ofspec.PodSpec.pkg/executor/util/merge.go::MergePodSpecunconditionally forwardedhostPID,hostNetwork,hostIPC, hostPath volumes,serviceAccountName, and containerprivilegedinto 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.Validatenow callsValidatePodSpecSafety("Function.spec.podspec", spec.PodSpec)after the existingspec.PodSpec == nilcheck.- 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.
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-v455-mv2v-5g92 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-v455-mv2v-5g92 in your dependencies?
Find it across Go, including transitive dependencies.