Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 0.29% for the current model date.
BlackTreeCVE Intelligencegeoserver · org.geoserver.web:gs-web-app
Official source article: GitHub GHSA-X4R9-GMW3-HXWW ↗. Check the applicable product and release in the original source.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
| Ecosystem and package | Affected range | First fixed version | Evidence |
|---|---|---|---|
| mavenorg.geoserver.web:gs-web-app | <= 2.26.3 | 2.26.4 | GitHub advisory ↗upstream repository advisory · 12 Jun 2026 |
| mavenorg.geoserver.web:gs-web-app | >= 2.27.0, <= 2.27.2 | 2.27.3 | GitHub advisory ↗upstream repository advisory · 12 Jun 2026 |
| mavenorg.geoserver:gs-main | <= 2.26.3 | 2.26.4 | GitHub advisory ↗upstream repository advisory · 12 Jun 2026 |
| mavenorg.geoserver:gs-main | >= 2.27.0, <= 2.27.2 | 2.27.3 | GitHub advisory ↗upstream repository advisory · 12 Jun 2026 |
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch availableGeoServer is an open source server that allows users to share and edit geospatial data. Prior to versions 2.26.4 and 2.27.3, a GeoServer that uses `ENTITY_RESOLUTION_ALLOWLIST` may allow attacker to perform unauthenticated Server-Side Request Forgery (SSRF). This vulnerability requires that GeoServer is set up to use a proxy base URL and the `ENTITY_RESOLUTION_ALLOWLIST` (default since 2.25.0). Versions 2.26.4 and 2.27.3 contain a fix. GeoServer installations are only affected by this vulnerability if they use a proxy base URL that does not contain a URL path or end with a slash. If the proxy base URL does not contain a path, adding a slash to the end of the URL will mitigate this vulnerability.
GeoServer is an open source server that allows users to share and edit geospatial data. Prior to versions 2.26.4 and 2.27.3, a GeoServer that uses `ENTITY_RESOLUTION_ALLOWLIST` may allow attacker to perform unauthenticated Server-Side Request Forgery (SSRF). This vulnerability requires that GeoServer is set up to use a proxy base URL and the `ENTITY_RESOLUTION_ALLOWLIST` (default since 2.25.0). Versions 2.26.4 and 2.27.3 contain a fix. GeoServer installations are only affected by this vulnerability if they use a proxy base URL that does not contain a URL path or end with a slash. If the proxy base URL does not contain a path, adding a slash to the end of the URL will mitigate this vulnerability.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
GeoServer is an open source server that allows users to share and edit geospatial data. Prior to versions 2.26.4 and 2.27.3, a GeoServer that uses `ENTITY_RESOLUTION_ALLOWLIST` may allow attacker to perform unauthenticated Server-Side Request Forgery (SSRF). This vulnerability requires that GeoServer is set up to use a proxy base URL and the `ENTITY_RESOLUTION_ALLOWLIST` (default since 2.25.0). Versions 2.26.4 and 2.27.3 contain a fix. GeoServer installations are only affected by this vulnerability if they use a proxy base URL that does not contain a URL path or end with a slash. If the proxy base URL does not contain a path, adding a slash to the end of the URL will mitigate this vulnerability.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
CWE-20: Improper Input Validation. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:LCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
Operational remediation based on structured source evidence.
Published 18 Jun 2026 · Last source change 18 Jun 2026, 15:26 UTC · CWE-20 · Improper Input Validation
Core structured fields are present and their contributing authorities are shown above.