Vulnerability in Kubernetes
CVE-2021-25735
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.054 (92.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 93rd percentile — 92.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.055 · newest: 0.054 · change: -0.001
Affected products
- Kubernetes — versions unspecified
Weakness classification (CWE)
Public proof-of-concept exploits
References
- groups.google.com/g/kubernetes-security-announce/c/FKAGqT4jx9Y (Mailing List, Third Party Advisory)
- github.com/kubernetes/kubernetes/issues/100096 (Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-25735?
- CVE-2021-25735 is a medium-severity vulnerability in Kubernetes, classified under CWE-372. CVSS score: 6.5/10. Published 2021-09-06.
- How severe is CVE-2021-25735?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-25735 known to be exploited?
- 30 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.