CVE-2021-25736

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.

CVSS 5.8 · Medium

External lookup

Potential internet exposure

Potential exposure only — not proof of vulnerability.Shodan results indicate potentially internet-exposed products, not confirmed vulnerable systems. They do not confirm that any returned system is vulnerable to CVE-2021-25736.

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Product CPE queries

Derived from this CVE's existing NVD CPE 2.3 records; the application, operating-system, or hardware part is retained.

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Exact CVE query

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Metadata

Canonical fields

NVD status

Unavailable

Published

Oct 30, 2023

Modified

Jun 17, 2026

Official record

Authoritative NVD record

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N

CWE IDs

Vendor classifications

How this vector reads

CVSS 3.1 base metrics decoded below. This explanation does not recalculate or change the NVD score.

Attack Vector (AV): Network. The vulnerable system can be reached across network boundaries.
Attack Complexity (AC): High. Successful exploitation depends on conditions outside the attacker's control.
Privileges Required (PR): High. The attacker needs significant administrative privileges.
User Interaction (UI): None. Exploitation does not require another user to act.
Scope (S): Changed. Impacts can cross into a different security authority.
Confidentiality Impact (C): High. There is a total or serious impact to this security property.
Integrity Impact (I): None. There is no direct impact to this security property.
Availability Impact (A): None. There is no direct impact to this security property.

Signals

Exploitation indicators

0 stored signals · no KEV · 0 OTX pulses