A Cross-site Scripting issue was discovered in PHOENIX CONTACT FL COMSERVER BASIC 232/422/485, FL COMSERVER UNI 232/422/485, FL COMSERVER BAS 232/422/485-T, FL COMSERVER UNI 232/422/485-T, FL COM SERVER RS232, FL COM SERVER RS485, and PSI-MODEM/ETH (running firmware versions prior to 1.99, 2.20, or 2.40). The cross-site scripting vulnerability has been identified, which may allow remote code execution.