GeoServer - Authentication Bypass (CVE-2025-27505)

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. Data from the CrowdSec community also indicates a gradual decrease in attacks targeting CVE-2025-27505. While still present in the wild, exploitation levels have dropped noticeably week-over-week. This may signal that the vulnerability is becoming less relevant or that defenses are improving fast enough for attackers to lose interest.

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