Frappe is a full-stack web application framework. Prior to 14.99.14 and 15.94.0, an attacker could craft a malicious signup URL for a frappe site which could lead to an open redirect (or reflected XSS, depending on the crafted payload) when a user signs up. This vulnerability is fixed in 14.99.14 and 15.94.0.
https://github.com/frappe/frappe/security/advisories/GHSA-7m8v-g2pr-h2f7
https://github.com/frappe/frappe/commit/22cac9dd240dc1fa00d4bab7e3887b70faf22bd1