onyx

onyx --cves cve-2021-25735

CVE-2021-25735

MEDPOCKubernetes
score
<0.1
cvss
6.5
epss
5.4%
published
2021-09-06
kev added
—
first seen

kube-apiserver contains a validation bypass caused by incomplete observation of node fields in Validating Admission Webhook, letting node updates bypass validation, exploit requires clusters to run such webhooks that deny based on old node state.

Timeline

How this CVE moved toward exploitation. Chart: last 30 days — trend score, EPSS, community mentions per day; hover the event lane.

events2021-09-06 — PublishedP2026-10-21 — Tracked by OnyxT2026-10-21 — Public PoCXscore2026-10-21: score <0.1<0.1epss2026-09-22: epss 5.5%2026-09-23: epss 5.5%2026-09-24: epss 5.5%2026-09-25: epss 5.5%2026-09-26: epss 5.5%2026-09-27: epss 5.5%2026-09-28: epss 5.5%2026-09-29: epss 5.5%2026-09-30: epss 5.5%2026-10-01: epss 5.5%2026-10-02: epss 5.5%2026-10-03: epss 5.5%2026-10-04: epss 5.5%2026-10-05: epss 5.5%2026-10-06: epss 5.5%2026-10-07: epss 5.5%2026-10-08: epss 5.5%2026-10-09: epss 5.4%2026-10-10: epss 5.4%2026-10-11: epss 5.4%2026-10-12: epss 5.4%2026-10-13: epss 5.4%2026-10-14: epss 5.4%2026-10-15: epss 5.4%2026-10-16: epss 5.4%2026-10-18: epss 5.4%2026-10-19: epss 5.4%2026-10-20: epss 5.4%2026-10-21: epss 5.4%5.4%mentions/day0no mentions in 30 days2026-09-22today
  1. Published
  2. Tracked by Onyx
  3. Public PoC

Exploit availability

Public PoC flagged by vulnx; no direct exploit link among the citations.

Weaknesses

CWE-372 NVD-CWE-Other

References 2