Low severity · published Sep 20, 2021
CVE-2021-25740
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
3.1
CVSS
2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.0% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KU
Kubernetes · Kubernetes
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-25740
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-25740
Mitigation
https://github.com/kubernetes/kubernetes/issues/103675
Mailing List
https://groups.google.com/g/kubernetes-security-announce/c/WYE9ptrhSLE
kubernetes.io
https://kubernetes.io/blog/2026/05/26/reconciling-unfixed-kubernetes-cves/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20211014-0001/
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