The ECOM Ethernet module in Koyo H0-ECOM, H0-ECOM100, H2-ECOM, H2-ECOM-F, H2-ECOM100, H4-ECOM, H4-ECOM-F, and H4-ECOM100 supports a maximum password length of 8 bytes, which makes it easier for remote attackers to obtain access via a brute-force attack.
https://exchange.xforce.ibmcloud.com/vulnerabilities/74876
http://www.us-cert.gov/control_systems/pdf/ICSA-12-102-02.pdf