In GLPI before version 9.5.2, the `install/install.php` endpoint insecurely stores user input into the database as `url_base` and `url_base_api`. These settings are referenced throughout the application and allow for vulnerabilities like Cross-Site Scripting and Insecure Redirection Since authentication is not required to perform these changes,anyone could point these fields at malicious websites or form input in a way to trigger XSS. Leveraging JavaScript it's possible to steal cookies, perform actions as the user, etc. The issue is patched in version 9.5.2.
https://github.com/glpi-project/glpi/security/advisories/GHSA-prvh-9m4h-4m79
https://github.com/glpi-project/glpi/commit/a8109d4ee970a222faf48cf48fae2d2f06465796