GeoServer is an open source server that allows users to share and edit geospatial data. Malicious Jiffle scripts can be executed by GeoServer, either as a rendering transformation in WMS dynamic styles or as a WPS process, that can enter an infinite loop to trigger denial of service. This vulnerability is fixed in 2.27.0, 2.26.3, and 2.25.7. This vulnerability can be mitigated by disabling WMS dynamic styling and the Jiffle process.

Affected: Maven: org.geoserver.web:gs-web-app, Maven: org.geoserver:gs-wms, Maven: org.geoserver.extension:gs-wps-core

### Summary Malicious Jiffle scripts can be executed by GeoServer, either as a rendering transformation in WMS dynamic styles or as a WPS process, that can enter an infinite loop to trigger denial of service.

### Details The Jiffle language supports multiple loop constructs that will cause its code block to be continuously executed until a certain condition is met. The Jiffle runtime should be updated to throw an exception if the script exceeds a certain number of loop iterations.

### Impact This vulnerability allows attackers to conduct denial-of-service attacks.

### Mitigation This vulnerability can be mitigated by disabling WMS dynamic styling (see [WMS Settings](https://docs.geoserver.org/latest/en/user/services/wms/webadmin.html#disabling-usage-of-dynamic-styling-in-getmap-getfeatureinfo-and-getlegendgraphic-requests)). If the WPS extension is installed, the Jiffle process must also be disabled to mitigate this vulnerability (see [WPS Settings](https://docs.geoserver.org/latest/en/user/services/wps/security.html#input-limits))

### References https://github.com/geosolutions-it/jai-ext/pull/307 https://osgeo-org.atlassian.net/browse/GEOS-11778

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in GeoServer ausnutzen, um Informationen offenzulegen oder einen Denial-of-Service auszulösen.