In Deciso OPNsense before 25.7.4, when creating an "Interfaces: Devices: Point-to-Point" entry, the value of the parameter ptpid is not sanitized of HTML-related characters/strings. This value is directly displayed when visiting the page/interfaces_assign.php, which can result in stored cross-site scripting. The attacker must be authenticated with at-least "Interfaces: PPPs: Edit" permission. This vulnerability has been addressed by the vendor in the product release notes as "ui: legacy_html_escape_form_data() was not escaping keys only data elements."