CVE-2021-25735
MEDIUMEPSS 92th pctlDescription
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.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
Exploit Intelligence
High risk: more likely to be exploited than 92% of all known CVEs.
References
Related Vulnerabilities
Other CWE-372 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2023-31127 | Critical | 9.0 | 0.9% | - | Fix |
| CVE-2020-27222 | High | 7.5 | 0.9% | - | - |
| CVE-2024-22590 | Critical | 9.1 | 0.6% | - | - |
| CVE-2023-4012 | High | 7.5 | 0.4% | - | Fix |
| CVE-2026-41388 | Medium | 6.5 | 0.3% | - | Fix |
| CVE-2023-36834 | Medium | 6.5 | 0.3% | - | - |
Common questions
How do I fix CVE-2021-25735?
Upgrade kubernetes on debian 11 to 1.20.5+really1.20.2-1 or later.
Is CVE-2021-25735 being actively exploited?
Not that we know of. CVE-2021-25735 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 5.5% is the estimated probability that it will be exploited in the next 30 days. That is higher than 92% of all scored CVEs.
How severe is CVE-2021-25735?
CVE-2021-25735 has a CVSS v3 base score of 6.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-25735 affect?
Published advisories record a fix for kubernetes (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-25735
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.