CVE-2023-4489: Silabs Z/ip Gateway SDK

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

The first S0 encryption key is generated with an uninitialized PRNG in Z/IP Gateway products running Silicon Labs Z/IP Gateway SDK v7.18.3 and earlier. This makes the first S0 key generated at startup predictable, potentially allowing network key prediction and unauthorized S0 network access.

Affected products

• Silabs Z/ip Gateway SDK: up to and including 7.18.03

Published 2023-12-14. Last modified 2026-06-17.