GeoServer is an open source software server written in Java that allows users to share and edit geospatial data. A stored cross-site scripting (XSS) vulnerability exists in versions prior to 2.23.4 and 2.24.1 that enables an authenticated administrator with workspace-level privileges to store a JavaScript payload in the GeoServer catalog that will execute in the context of another user's browser when viewed in the WMS GetMap SVG Output Format when the Simple SVG renderer is enabled. Access to the WMS SVG Format is available to all users by default although data and service security may limit users' ability to trigger the XSS. Versions 2.23.4 and 2.24.1 contain a fix for this issue.