CVE-2026-20212

A vulnerability in the Silicon One integration for Cisco Nexus 9000 Series Switches could allow an unauthenticated, remote attacker to execute code with root privileges. This vulnerability exists because TCP ports 43210 and 43211 are accessible in the default Layer 3 (L3) virtual routing and forwarding (VRF). A successful exploit could allow the attacker to connect to an affected device and send crafted input that could be executed as code with root privileges. The exploitation of this vulnerability could also cause the S1HAL process to crash, which could cause the device to reload.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9k-s1-rce-EH8dEtr

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-02 17:17

Updated : 2026-09-03 13:04

NVD link : CVE-2026-20212

Mitre link : CVE-2026-20212

CVE.ORG link : CVE-2026-20212

JSON object : View

Products Affected

No product.

CWE

CWE-1327

Binding to an Unrestricted IP Address

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