Summary Multiple OGC request parameters allow Remote Code Execution (RCE) by unauthenticated users through specially crafted input against a default GeoServer installation due to unsafely evaluating property names as XPath expressions. Details The GeoTools library API that GeoServer calls evaluates property/attribute names for feature types in a way that unsafely passes them to the commons-jxpath library which can execute arbitrary code when evaluating XPath expressions. This XPath evaluation is intended to be used only by complex feature types (i.e., Application Schema data stores) but is incorrectly being applied to simple feature types as well which makes this vulnerability apply to ALL GeoServer instances. PoC No public PoC is provided but this vulnerability has been confirmed to be exploitable through WFS GetFeature, WFS GetPropertyValue, WMS GetMap, WMS GetFeatureInfo, WMS GetLegendGraphic and WPS Execute requests. Impact This vulnerability can lead to executing arbitrary code. Workaround A workaround exists by removing the gt-complex-x.y.jar file from the GeoServer where x.y is the GeoTools version (e.g., gt-complex-31.1.jar if running GeoServer 2.25.1). This will remove the vulnerable code from GeoServer but may break some GeoServer functionality or prevent GeoServer from deploying if the gt-complex module is needed by an extension you are using: Mitigation for geoserver.war deploy: Stop the application server Unzip geoserver.war into a directory Locate the file…Read More