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.
https://talosintelligence.com/vulnerability_reports/TALOS-2019-0963