CVE-2021-25740
low
CVSS v3
3.1
CVSS v4 NEW
—
VIR risk
3.1
Description
A security issue was discovered with Kubernetes that could enable users to send network traffic to locations they would otherwise not have access to via a confused deputy attack.
Predictions
Exploit likelihood
42%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Arch Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 1.20.5+really1.20.2-1 |
| sid | Fixed | 1.20.5+really1.20.2-1 |
| forky | Fixed | 1.20.5+really1.20.2-1 |
| bullseye | Fixed | 1.20.5+really1.20.2-1 |
| bookworm | Fixed | 1.20.5+really1.20.2-1 |
Package impact
| Ecosystem | Package | Vulnerable | Fixed |
|---|---|---|---|
| Go | k8s.io/kubernetes | <=1.22.2 | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| kubernetes | kubernetes | - | |
References
- https://www.suse.com/security/cve/CVE-2021-25740.html
- https://nvd.nist.gov/vuln/detail/CVE-2021-25740
- https://github.com/kubernetes/kubernetes/issues/103675
- https://github.com/kubernetes/kubernetes
- https://groups.google.com/g/kubernetes-security-announce/c/WYE9ptrhSLE
- https://security.netapp.com/advisory/ntap-20211014-0001
- https://security-tracker.debian.org/tracker/CVE-2021-25740
- https://kubernetes.io/blog/2026/05/26/reconciling-unfixed-kubernetes-cves/
- https://security.netapp.com/advisory/ntap-20211014-0001/
CWEs
CWE-441 CWE-610
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.