Vulnerability Intelligence Report
Cisco Nexus 3000 and 9000 Series Switches Silicon One Hardware Abstraction Layer Remote Code Execution Vulnerability
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.
No Active Exploit Signals
CVSS Base Score
9.8
CRITICAL
Exploitability:3.9
Impact Score:5.9
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-1327 ↗Binding to an Unrestricted IP Address
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Cisco | Cisco NX-OS Software | 10.3(1) (affected), 10.3(2) (affected), 10.3(3) (affected), 10.4(1) (affected), 10.3(99w) (affected), 10.3(3w) (affected), 10.3(99x) (affected), 10.3(3o) (affected), 10.3(4) (affected), 10.3(3p) (affected), 10.3(4a) (affected), 10.4(2) (affected), 10.3(3q) (affected), 10.3(5) (affected), 10.4(3) (affected), 10.3(3x) (affected), 10.3(4g) (affected), 10.5(1) (affected), 10.3(3r) (affected), 10.3(6) (affected), 10.4(4) (affected), 10.3(4h) (affected), 10.5(2) (affected), 10.3(7) (affected), 10.4(5) (affected), 10.5(3) (affected), 10.4(4g) (affected), 10.5(4) (affected), 10.6(1) (affected), 10.5(3t) (affected), 10.3(8) (affected), 10.4(6) (affected), 10.5(3s) (affected), 10.5(3e) (affected), 10.5(3o) (affected), 10.6(1s) (affected), 10.6(2) (affected), 10.5(3p) (affected), 10.3(9) (affected), 10.6(2s) (affected), 10.6(3) (affected), 10.4(7) (affected), 10.5(5) (affected), 10.6(2n) (affected), 10.6(3s) (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Cisco Systems, Inc. · Hosted Service · USA |
| Reserved | 2025-10-08T11:59:15 |
| Published | 2026-09-02T16:13:08 |
| Last Updated | 2026-09-03T03:56:34 |
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