# CVE-2026-58400: GeoNetwork remote code execution via unsafe Saxon XSLT processor

Source: https://junglewise.ai/threats/cve-2026-58400-geonetwork-remote-code-execution-via-unsafe-saxon-xslt-processor  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-03. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-58400 · Severity: critical · CVSS 9.1 · Published 2026-09-03

GeoNetwork is a web-based catalog application that manages geographic and spatial data resources. The Saxon XSLT processor, which GeoNetwork uses to render formatters for display purposes, is misconfigured and allows users with formatter-upload privileges to execute arbitrary system commands with the full privileges of the GeoNetwork application. This could allow an attacker to compromise the server, steal data, or disrupt operations.

## Quick answers

**Is CVE-2026-58400 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58400 being exploited in the wild.

**How severe is CVE-2026-58400?** Critical severity, with a CVSS score of 9.1, published 3 September 2026.

**Which products and versions are affected?** GeoNetwork GeoNetwork 4.4.0–4.4.11, 4.2.0–4.2.16.

**Is there a fix for CVE-2026-58400?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-58400 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-58400?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability stems from unsafe configuration of the Saxon XSLT processor: secure processing (FEATURE_SECURE_PROCESSING) is disabled and Java extension functions (ALLOW_EXTERNAL_FUNCTIONS) are not restricted. This allows any XSLT stylesheet loaded by GeoNetwork to invoke java.lang.Runtime.exec() or java.lang.ProcessBuilder directly. An attacker with sufficient privileges to upload a formatter can craft a malicious .xsl file containing Java extension calls that execute arbitrary OS commands. The attack requires formatter-upload privileges but has no network restriction—the payload is processed server-side during stylesheet rendering. Patches are available in GeoNetwork 4.4.12 and 4.2.17.

## Affected products

- GeoNetwork GeoNetwork 4.4.0–4.4.11, 4.2.0–4.2.16

## Timeline

- 2026-09-03: disclosed

## References

- [https://docs.geonetwork-opensource.org/4.2/overview/change-log/version-4.2.17](https://docs.geonetwork-opensource.org/4.2/overview/change-log/version-4.2.17)
- [https://docs.geonetwork-opensource.org/4.4/overview/change-log/version-4.4.12](https://docs.geonetwork-opensource.org/4.4/overview/change-log/version-4.4.12)