Vulnerability · Published Oct 30, 2023 · Assigned by kubernetes

CVE-2021-25736Windows kube-proxy LoadBalancer contention

Medium 5.8

In plain English

A medium-severity security flaw in Kubernetes from Kubernetes. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 60% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.8Medium

Exploit odds (30 days)0.9%top 39.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Kube-proxy on Windows can unintentionally forward traffic to local processes listening on the same port (“spec.ports[*].port”) as a LoadBalancer Service when the LoadBalancer controller does not set the “status.loadBalancer.ingress[].ip” field. Clusters where the LoadBalancer controller sets the “status.loadBalancer.ingress[].ip” field are unaffected.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	k8s.io/kubernetes	1.21.0	GHSA-35c7-w35f-xwgh
Go	k8s.io/kubernetes	1.21.0	GO-2023-2159

Affected products (as reported)

Vendor	Product	Versions
Kubernetes	Kubernetes	0 – through v1.20.5

Weakness: CWE-114 · Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N

In plain English

Official description

Affected packages & fixed versions

Affected products (as reported)

References