CVE-2021-25737
Published:September 06, 2021
Updated:May 17, 2026
A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs.
Affected Packages
k8s.io/kubernetes (GO):
Affected version(s) >=v1.19.0 <v1.19.11Fix Suggestion:
Update to version v1.19.11k8s.io/kubernetes (GO):
Affected version(s) >=v1.21.0 <v1.21.1Fix Suggestion:
Update to version v1.21.1k8s.io/kubernetes (GO):
Affected version(s) >=v1.20.0 <v1.20.7Fix Suggestion:
Update to version v1.20.7k8s.io/kubernetes (GO):
Affected version(s) >=v1.16.0 <v1.18.19Fix Suggestion:
Update to version v1.18.19Related Resources (7)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.1
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
2.7
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
CVSS v2
Base Score:
4.9
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
NONE
Weakness Type (CWE)
EPSS
Base Score:
0.38