# CVE-2025-27505: GeoServer - Authentication Bypass

> Live exploitation tracking for CVE-2025-27505 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2025-27505

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 5.3
- **Public exploit available:** Yes
- **Affected products:** GeoServer
- **Weaknesses:** CWE-862 (Missing Authorization)
- **Tags:** web_application

## Description

GeoServer is an open source server that allows users to share and edit geospatial data. It is possible to bypass the default REST API security and access the index page. The REST API security handles rest and its subpaths but not rest with an extension (e.g., rest.html). The REST API index can disclose whether certain extensions are installed. This vulnerability is fixed in 2.26.3 and 2.25.6. As a workaround, in ${GEOSERVER_DATA_DIR}/security/config.xml, change the paths for the rest filter to /rest.*,/rest/** and change the paths for the gwc filter to /gwc/rest.*,/gwc/rest/** and restart GeoServer.

## CrowdSec analysis

[CVE-2025-27505](https://euvd.enisa.europa.eu/vulnerability/CVE-2025-27505) is a security vulnerability in GeoServer that allows attackers to bypass REST API security controls by accessing the API index page with certain file extensions, such as .html. This flaw can expose information about installed extensions, potentially aiding reconnaissance and further attacks. The issue is resolved in versions 2.26.3 and 2.25.6.

CrowdSec has been tracking this vulnerability and its exploits since 16th of July 2025.

Data from the CrowdSec community indicates that exploitation of CVE-2025-27505 is highly selective and intelligence-driven. Threat actors use advanced reconnaissance and carefully choose their targets, often as part of sophisticated campaigns or advanced persistent threat operations.
Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2025-27505 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2025-27505 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers exploit this vulnerability by directly accessing the `/rest.html` or `/geoserver/rest.html` endpoints, exposing sensitive GeoServer configuration information without proper authorization.

## Timeline

- 2025-06-10: CVE Published. CVE-2025-27505 is published to NVD.
- 2025-07-16: Rule Released. CrowdSec releases a rule to detect CVE-2025-27505 exploitation attempts against the CrowdSec Network.
- 2025-07-21: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2025-27505 for the first time.

## References

- https://osgeo-org.atlassian.net/browse/GEOS-11776
- https://github.com/geoserver/geoserver/security/advisories/GHSA-h86g-x8mm-78m5
- https://osgeo-org.atlassian.net/browse/GEOS-11664
- https://github.com/geoserver/geoserver/pull/8170
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-27505.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2025-27505) follows observed exploitation activity for CVE-2025-27505. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.