CVE-2025-30220 is a critical vulnerability affecting GeoServer, an open-source server platform used for sharing and editing geospatial data. The vulnerability arises from improper restriction of XML External Entity (XXE) references within the GeoTools Schema class, which relies on the Eclipse XSD library to represent schema data structures. Specifically, when GeoServer processes XML documents that reference external XML schemas, the gt-xsd-core Schemas class fails to utilize the EntityResolver provided by the ParserHandler, if configured. This flaw allows an attacker to craft malicious XML input that can trigger the XXE exploit, potentially leading to unauthorized disclosure of sensitive information, partial integrity compromise, and availability impact. Additionally, users of the gt-wfs-ng DataStore are affected due to improper use of the ENTITY_RESOLVER connection parameter. The vulnerability affects multiple versions of GeoServer (prior to 2.27.1, 2.26.3, and 2.25.7) and GeoTools (versions before 33.1, 32.3, 31.7, and 28.6.1). The CVSS v3.1 score is 9.9 (critical), reflecting network exploitable conditions without authentication or user interaction, with high confidentiality impact, low integrity impact, and low availability impact. No known exploits are currently reported in the wild. The root cause is CWE-611 (Improper Restriction of XML External Entity Reference) and CWE-918 (Server-Side Request Forgery), indicating that the vulnerability could be leveraged to perform SSRF attacks or access internal resources via crafted XML payloads. This vulnerability is particularly dangerous because GeoServer is often exposed to external networks to serve geospatial data, making it a high-value target for attackers seeking to exfiltrate sensitive geographic or infrastructure information or disrupt services.

For European organizations, the impact of CVE-2025-30220 can be significant, especially for those relying on GeoServer for critical geospatial data services in sectors such as urban planning, transportation, environmental monitoring, defense, and utilities. Confidentiality is the most affected aspect, as attackers could exploit the XXE vulnerability to read arbitrary files on the server or perform SSRF attacks to access internal network resources, potentially exposing sensitive or classified geospatial data. Integrity impact is limited but could allow partial manipulation or disruption of data processing. Availability impact is low but possible if the exploit leads to denial-of-service conditions. Given the criticality of geospatial data in infrastructure and government services, exploitation could lead to operational disruptions, loss of trust, and regulatory compliance issues under GDPR if personal or sensitive data is exposed. The vulnerability’s network-exploitable nature without authentication increases risk, especially for publicly accessible GeoServer instances. European organizations with public-facing geospatial services or integrated GIS platforms are at heightened risk.

1. Immediate patching: Upgrade GeoServer installations to versions 2.27.1, 2.26.3, or 2.25.7 and GeoTools to versions 33.1, 32.3, 31.7, or 28.6.1 as applicable. 2. Configuration review: Ensure that XML parsers used by GeoServer and GeoTools are configured to disable external entity resolution and DTD processing unless explicitly required and safely managed. 3. Network segmentation: Restrict GeoServer’s network access to limit outbound connections, preventing SSRF exploitation from reaching internal resources. 4. Input validation: Implement strict validation and sanitization of all XML inputs, especially those that reference external schemas. 5. Monitoring and logging: Enable detailed logging of XML processing errors and monitor for unusual outbound requests or access patterns indicative of exploitation attempts. 6. Access controls: Limit exposure of GeoServer interfaces to trusted networks or VPNs where possible. 7. Incident response preparedness: Develop and test incident response plans specific to geospatial data breaches and XXE exploitation scenarios. 8. Vendor advisories: Stay updated with GeoServer and GeoTools security advisories for any further patches or mitigation guidance.