WeGIA is a web manager for charitable institutions. Prior to 3.8.7, a stored cross-site scripting vulnerability in `saude/historico_prontuarios.php` arises because the `textoProntuario` field accepts arbitrary HTML or JavaScript without proper sanitization. An attacker able to create or access a patient's medical record can submit the field through `POST /controle/control.php` with `nomeClasse=SaudeControle`, `metodo=alterarProntuario`, and `id_fichamedica`. The stored content is rendered when another user accesses `/html/saude/historico_prontuarios.php` with `id_historico`, automatically executing attacker-controlled JavaScript in the victim's browser. The vulnerability permits session cookie theft and potential account compromise depending on the victim's privileges. This issue is fixed in version 3.8.7.