Home/CVE/A security issue was discovered with Kubernetes that could enable users to send network traffic to locations they would
CVE

CVE-2021-25740

A security issue was discovered with Kubernetes that could enable users to send network traffic to locations they would

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.

LOW · CVSS 3.1 EPSS 0.00519
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules8 YARA rules0
⬡

Weakness Classification

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

Affected Products & Versions

1
kubernetesall versions
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Go k8s.io/kubernetes LOW
◈

Sigma Hunt Rules

8
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumKubernetes Events Deleted
productmediumKubernetes Admission Controller Modification
productmediumKubernetes CronJob/Job Modification
productmediumKubernetes Potential Enumeration Activity
productmediumKubernetes Secrets Modified or Deleted
productmediumKubernetes Rolebinding Modification
▣

Scoring & Timeline

3.1
LOW · CVSS v3.1 · jordan@liggitt.net
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD20 Sep 2021 · 05:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
🔗

References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/kubernetes/kubernetes/issues/103675MitigationThird Party Advisory
https://groups.google.com/g/kubernetes-security-announce/c/WYE9ptrhSLEMailing ListMitigationThird Party Advisory
https://security.netapp.com/advisory/ntap-20211014-0001/Third Party Advisory
Intelligence Graph · click any node to traverse
CVETechnique ActorTool Family
drag to reposition · click any node to traverse · button top-right enlarges
External lookups - second-class, for what we don’t hold ourselves
NVDCVE.orgCISAVulnersExploit-DBGitHub PoCVulnCheck KEVGreyNoise
Vulnerabilities
CISA KEV catalog
CWE weaknesses
CAPEC attack patterns
Package vulnerabilities
Threat intelligence
Threat actors
Tools & malware
ATT&CK techniques
IOCs
Detection & defense
Sigma rules
YARA rules
Atomic Red Team tests
D3FEND countermeasures
Compliance
NIST 800-53
ISO 27001:2022
SOC 2 TSC
PCI-DSS v4.0
CIS Controls v8.1
About
All capabilities
Live statistics
Data sources
Privacy policy
Terms of service
threatengine.sh  ·  Open-source threat intelligence platform  ·  100+ authoritative sources  ·  Every fact traces to its origin