Cisco Unified Communications Products Security Hardening Release: October 2026
cisco-sa-voice-hardening-twgbH9e3
Summary
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. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.
Security Impact Rating: Critical CVE: CVE-2026-20212
Products covered
A separate affected-products list was not included in the collected bulletin.
Remediation
Cisco has released software updates that address this vulnerability.
CVEs in this advisory 1
Updates
- Published by Cisco
The publication date reported by the vendor.
- Added to SecurityAlert
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- Confirmed at the source
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