CVE catalog
CVE-2021-25735
kubernetes: CVE-2021-25735
- Severity
- Medium · CVSS 6.5
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 5.38% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | kubernetes | sid | 1.36.4+ds-1 | fixed |
| Debian | kubernetes | forky | 1.36.4+ds-1 | fixed |
| Debian | kubernetes | trixie | 1.32.3+ds-2 | fixed |
| Debian | kubernetes | bookworm | 1.20.5+really1.20.2-1.1+deb12u1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | kubernetes | source | sid | 1.20.5+really1.20.2-1 | not yet assigned | Not reported | [990793] |
| Debian | kubernetes | source | forky | 1.20.5+really1.20.2-1 | not yet assigned | Not reported | [990793] |
| Debian | kubernetes | source | trixie | 1.20.5+really1.20.2-1 | not yet assigned | Not reported | [990793] |
| Debian | kubernetes | source | bookworm | 1.20.5+really1.20.2-1 | not yet assigned | Not reported | [990793] |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [kubernetes-client]Fixed
Source package: [kubernetes]
Details (2)
1.20.5+really1.20.2-1.1+deb12u1· amd64 · bookwormFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · bookworm; dsa · kubernetes · debian · 12
1.20.5+really1.20.2-1.1+deb12u1· arm64 · bookwormFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · bookworm; dsa · kubernetes · debian · 12
[Debian 13 (Trixie)]
- [golang-k8s-kubectl-dev]Fixed
Source package: [kubernetes]
Details (2)
1.32.3+ds-2· all · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
1.32.3+ds-2· all · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
- [kubectl]Fixed
Source package: [kubernetes]
Details (2)
1.32.3+ds-2· amd64 · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
1.32.3+ds-2· arm64 · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
- [kubernetes-client]Fixed
Source package: [kubernetes]
Details (2)
1.32.3+ds-2· amd64 · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
1.32.3+ds-2· arm64 · trixieFixed · Fixed:
1.20.5+really1.20.2-1dsa · kubernetes · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2025_15424-1.json]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-25735]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-25735]
- [https://security-tracker.debian.org/tracker/CVE-2021-25735]
- [https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-25735.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2022/wid-sec-w-2022-0510.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]