GeoServer is an open source software server written in Java that allows users to share and edit geospatial data. In affected versions the welcome and about page includes version and revision information about the software in use (including library and components used). This information is sensitive from a security point of view because it allows software used by the server to be easily identified. This issue has been patched in version 2.26.0 and all users are advised to upgrade. There are no known workarounds for this vulnerability.