title: Kubernetes API server follows unvalidated redirects from streaming Kubelet endpoints
description: Improper validation of URL redirection in the Kubernetes API server in versions prior to v1.14.0 allows an attacker-controlled Kubelet to redirect API server requests from streaming endpoints to arbitrary hosts. Impacted API servers will follow the redirect as a GET request with client-certificate credentials for authenticating to the Kubelet.
problem types: CWE-601 URL Redirection to Untrusted Site ('Open Redirect')
affected:
{
product: Kubernetes
vendor: Kubernetes
versions:
lessThan: v1.14.0, status: affected, version: v1.14, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 2.6
baseSeverity: LOW
confidentialityImpact: LOW
integrityImpact: NONE
privilegesRequired: HIGH
scope: CHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:L/I:N/A:N
version: 3.1
]
workarounds: For Kubernetes versions >= v1.10.0, the ValidateProxyRedirects feature can be manually enabled with the kube-apiserver flag --feature-gates=ValidateProxyRedirects=true