Medium severity6.5NVD Advisory· Published Sep 6, 2021· Updated Jun 17, 2026
CVE-2021-25735
CVE-2021-25735
Description
A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
k8s.io/kubernetesGo | >= 1.20.0, < 1.20.6 | 1.20.6 |
k8s.io/kubernetesGo | >= 1.19.0, < 1.19.10 | 1.19.10 |
k8s.io/kubernetesGo | < 1.18.18 | 1.18.18 |
Affected products
29cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:*+ 1 more
- cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:*range: <1.18.18
- (no CPE)range: unspecified
- osv-coords27 versionspkg:apk/chainguard/kubeflow-pipelinespkg:apk/chainguard/kubeflow-pipelines-apiserverpkg:apk/chainguard/kubeflow-pipelines-cache-deployerpkg:apk/chainguard/kubeflow-pipelines-cache-deployer-compatpkg:apk/chainguard/kubeflow-pipelines-cache_serverpkg:apk/chainguard/kubeflow-pipelines-frontendpkg:apk/chainguard/kubeflow-pipelines-metadata-envoy-configpkg:apk/chainguard/kubeflow-pipelines-metadata-writerpkg:apk/chainguard/kubeflow-pipelines-metadata-writer-compatpkg:apk/chainguard/kubeflow-pipelines-persistence_agentpkg:apk/chainguard/kubeflow-pipelines-scheduledworkflowpkg:apk/chainguard/kubeflow-pipelines-viewer-crd-controllerpkg:apk/chainguard/kubernetes-dns-node-cache-1.17pkg:apk/wolfi/kubeflow-pipelinespkg:apk/wolfi/kubeflow-pipelines-apiserverpkg:apk/wolfi/kubeflow-pipelines-cache-deployerpkg:apk/wolfi/kubeflow-pipelines-cache-deployer-compatpkg:apk/wolfi/kubeflow-pipelines-cache_serverpkg:apk/wolfi/kubeflow-pipelines-frontendpkg:apk/wolfi/kubeflow-pipelines-metadata-envoy-configpkg:apk/wolfi/kubeflow-pipelines-metadata-writerpkg:apk/wolfi/kubeflow-pipelines-metadata-writer-compatpkg:apk/wolfi/kubeflow-pipelines-persistence_agentpkg:apk/wolfi/kubeflow-pipelines-scheduledworkflowpkg:apk/wolfi/kubeflow-pipelines-viewer-crd-controllerpkg:golang/k8s.io/kubernetespkg:rpm/opensuse/govulncheck-vulndb&distro=openSUSE%20Tumbleweed
< 0+ 26 more
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: < 0
- (no CPE)range: >= 1.20.0, < 1.20.6
- (no CPE)range: < 0.0.20250807T150727-1.1
Patches
Vulnerability mechanics
References
9- github.com/kubernetes/kubernetes/issues/100096nvdPatchThird Party AdvisoryWEB
- github.com/advisories/GHSA-g42g-737j-qx6jghsaADVISORY
- groups.google.com/g/kubernetes-security-announce/c/FKAGqT4jx9YnvdMailing ListThird Party AdvisoryWEB
- nvd.nist.gov/vuln/detail/CVE-2021-25735ghsaADVISORY
- bugzilla.redhat.com/show_bug.cgighsaWEB
- github.com/kubernetes/kubernetes/commit/00e81db174ef7aca497be5f42d87e46d14df2a90ghsaWEB
- github.com/kubernetes/kubernetes/pull/99946ghsaWEB
- pkg.go.dev/k8s.io/[email protected]/cmd/kube-apiserverghsaWEB
- sysdig.com/blog/cve-2021-25735-kubernetes-admission-bypassghsaWEB
News mentions
0No linked articles in our index yet.