CVE-2018-16558: Siemens SIMATIC s7-1500 Firmware

High severity, CVSS 7.5. EPSS: 2% chance of exploitation in the next 30 days.

A vulnerability has been identified in SIMATIC S7-1500 CPU (All versions >= V2.0 and < V2.5), SIMATIC S7-1500 CPU (All versions <= V1.8.5). Specially crafted network packets sent to port 80/tcp or 443/tcp could allow an unauthenticated remote attacker to cause a Denial-of-Service condition of the device. The security vulnerability could be exploited by an attacker with network access to the affected systems on port 80/tcp or 443/tcp. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise availability of the device. At the time of advisory publication no public exploitation of this security vulnerability was known.

Affected products

• Siemens SIMATIC s7-1500 Firmware: up to and including 1.8.5; from 2.0, before 2.5 (fixed in 2.5)

Published 2019-04-17. Last modified 2026-06-17.