Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 64.9%; technical severity is CVSS 9.8.
GeoServer is an open source server that allows users to share and edit geospatial data. From version 2.26.0 to before 2.26.2 and before 2.25.6, 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. This issue has been patched in GeoServer 2.25.6, GeoServer 2.26.3, and GeoServer 2.27.0.
Who should care
- Teams operating Geoserver, GeoServer
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether Geoserver, GeoServer is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Vendor advisory from github.com
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Treatment intelligence
Remediation intelligence
Vendor sources are listed before government and third-party guidance. Confirm product applicability and change prerequisites before deployment.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-611
- Affected versions
- Geoserver Geoserver (End Excluding 2.25.6 | Start Including 2.26.0, End Excluding 2.26.2); OSGeo GeoServer
- Fixed versions
- Geoserver Geoserver (Fixed from 2.25.6, 2.26.2)
- Published
- 25 November 2025
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 64.9%
- Signal calculated at 81