The application is vulnerable to Stored Cross-Site Scripting (XSS) in the endpoint /sofer/DocumentService.asc/SaveAnnotation, where input data transmitted via the POST method in the parameters author and text are not adequately sanitized and validated. This allows for the injection of malicious JavaScript code. The vulnerability was identified in the function for adding new annotations while editing document content. Reporters inform that the vulnerability has been removed in software versions above 11.1.x. Previous versions may also be vulnerable, but this has not been confirmed.