Description

An XML External Entity (XXE) vulnerability was identified. The application accepts XML input through a specific endpoint /geoserver/wms operation GetMap. However, this input is not sufficiently sanitized or restricted, allowing an attacker to define external entities within the XML request.

An XML External Entity attack is a type of attack that occurs when XML input containing a reference to an external entity is processed by a weakly configured XML parser. This attack may lead to the disclosure of confidential data, denial of service, port scanning from the perspective of the machine where the parser is located, and other system impacts.

By exploiting this vulnerability, an attacker can: - Read arbitrary files from the server's file system. - Conduct Server-Side Request Forgery (SSRF) to interact with internal systems. - Execute Denial of Service (DoS) attacks by exhausting resources.

Resolution

Update to GeoServer 2.25.6, GeoServer 2.26.3, or GeoServer 2.27.0.

Impact

The XXE vulnerability can be used to retrieve arbitrary files from the server's file system.

Reference

https://osgeo-org.atlassian.net/browse/GEOS-11682 XBOW-024-081

Disclaimer

This vulnerability was detected using XBOW, a system that autonomously finds and exploits potential security vulnerabilities. The finding has been thoroughly reviewed and validated by a security researcher before submission. While XBOW is intended to work autonomously, during its development human experts ensure the accuracy and relevance of its reports.

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:

1. Stop the application server 2. Unzip geoserver.war into a directory 3. Locate the file WEB-INF/lib/gt-complex-x.y.jar and remove 4. Zip the directory into a new geoserver.war 5. Restart the application server

Mitigation for GeoServer binary:

1. Stop Jetty 2. Locate the file webapps/geoserver/WEB-INF/lib/gt-complex-x.y.jar and remove 3. Restart Jetty

The following extensions and community modules are known to have a direct dependency on gt-complex jar and are not expected function properly without it. This is not comprehensive list and additional GeoServer functionality may be dependent on the availability of gt-complex jar: Extensions: Application Schema, Catalog Services for the Web, MongoDB Data Store Community Modules: Features-Templating, OGC API Modules, Smart Data Loader, SOLR Data Store

Mitigation available for prior releases patching three jars in your existing install:

1. Patched gt-app-schema, gt-complex and gt-xsd-core jars may be downloaded for GeoServer: 2.25.1, 2.24.3, 2.24.2, 2.23.2, 2.22.2, 2.21.5, 2.21.4,2.20.7, 2.20.4, 2.19.2, 2.18.0. As example the 2.25.1 page links to geoserver-2.25.1-patches.zip download on source forge.

2. Unzip the geoserver-x.y.z-patches.zip which contains three jars that have been patched to configure commons-jxpath with an empty function list prior to use. These files are drop-in replacements with identical file names to those they are replacing.

3. Follow the instructions above to locate WEB-INF/lib folder and replace the existing gt-app-schema, gt-complex and gt-xsd-core jars with those supplied by the patch.

References https://github.com/geotools/geotools/security/advisories/GHSA-w3pj-wh35-fq8w https://osgeo-org.atlassian.net/browse/GEOT-7587 https://github.com/geotools/geotools/pull/4797 https://github.com/Warxim/CVE-2022-41852?tab=readme-ov-file#workaround-for-cve-2022-41852

Impact Programs using jt-jiffle, and allowing Jiffle script to be provided via network request, are susceptible to a Remote Code Execution as the Jiffle script is compiled into Java code via Janino, and executed. In particular, this affects the downstream GeoServer project.

Patches Version 1.2.22 will contain a patch that disables the ability to inject malicious code into the resulting script.

Workarounds Negate the ability to compile Jiffle scripts from the final application, by removing janino-x.y.z.jar from the classpath.

References None.