CVE-2019-5178: Wago PFC200 Firmware

High severity, CVSS 7.8. EPSS: 0.7% chance of exploitation in the next 30 days.

An exploitable stack buffer overflow vulnerability vulnerability exists in the iocheckd service ‘I/O-Check’ functionality of WAGO PFC 200 Firmware version 03.02.02(14). An attacker can send a specially crafted packet to trigger the parsing of this cache file. The destination buffer sp+0x440 is overflowed with the call to sprintf() for any hostname values that are greater than 1024-len(‘/etc/config-tools/change_hostname hostname=‘) in length. A hostname value of length 0x3fd will cause the service to crash.

Affected products

• Wago PFC200 Firmware: version 03.02.02(14) only

Published 2020-03-12. Last modified 2026-06-17.