CVE-2026-22924: Siemens SIMATIC Cn 4100 Firmware

Critical severity, CVSS 9.1. EPSS: 0.3% chance of exploitation in the next 30 days.

A vulnerability has been identified in SIMATIC CN 4100 (All versions < V5.0). The affected application does not properly restrict unauthenticated connections and is susceptible to resource exhaustion conditions. This could allow an attacker to disrupt normal operations or perform unauthorized actions, potentially impacting system availability and integrity.

Affected products

• Siemens SIMATIC Cn 4100 Firmware: before 5.0 (fixed in 5.0)

Published 2026-05-12. Last modified 2026-06-29.