IPFire versions prior to 2.29 (Core Update 198) contain a stored cross-site scripting (XSS) vulnerability that allows an authenticated attacker to inject arbitrary JavaScript code through the TLS_HOSTNAME parameter when adding a new DNS entry. When a user adds a DNS entry, the application issues an HTTP POST request to /cgi-bin/dns.cgi and the TLS hostname is provided in the TLS_HOSTNAME parameter. The value of this parameter is stored and later rendered in the web interface without proper sanit