CVE•Published 2021-09-20•Modified 2026-06-01•0 articles on news•6 live references•NVD data

CVE-2021-25740Kubernetes · Kubernetes

Vulnerability data via NVD (ingested)

CVSS v3.1

3.1

LOW

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

EPSS percentile

Exploit Prediction Scoring System · top 34% of all CVEs

Weaknesses (CWE)

CWE-441Unintended Proxy or Intermediary ('Confused Deputy')CWE-610Externally Controlled Reference to a Resource in Another Sphere

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.

Timeline

Published 2021-09-20

Modified 2026-06-01

External references

NVD MITRE Exploit-DB Sploitus trickest/cve VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2021-25740

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Kubernetes Kubernetes"

All exposed Kubernetes Kubernetes instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Kubernetes"

HTTP body or banner mentions "Kubernetes" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2021-25740