GFI MailEssentials AI < 22.4 POP2Exchange POP3 Server Login Stored XSS

GFI MailEssentials AI versions prior to 22.4 contain a stored cross-site scripting vulnerability in the POP2Exchange configuration endpoint. An authenticated user can supply HTML/JavaScript in the POP3 server login field within the JSON \"popServers\" payload to /MailEssentials/pages/MailSecurity/POP2Exchange.aspx/Save, which is stored and later rendered in the management interface, allowing script execution in the context of a logged-in user.