Cross-site scripting (XSS) vulnerability in mailpost.exe in MailPost 5.1.1sv, and possibly earlier versions, when debug mode is enabled, allows remote attackers to execute arbitrary web script or HTML via the append parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/17953
https://euvd.enisa.europa.eu/vulnerability/EUVD-2004-1098
http://www.securityfocus.com/bid/11596