CiscoCVE-2026-20212
Cisco NX-OS Software: remote code execution
Critical9.8CVE-2026-20212 · Published Sep 2, 2026 · updated Sep 3, 2026
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.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Cisco NX-OS Software Product | <= 10.3(1) | No fix yet |
| <= 10.3(2) | No fix yet | |
| <= 10.3(3) | No fix yet | |
| <= 10.4(1) | No fix yet |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-1327
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