CVE-2025-15373 is a server-side request forgery vulnerability identified in EyouCMS, a content management system, specifically impacting versions 1.7.0 through 1.7.7. The vulnerability resides in the saveRemote function of the application/function.php file, which improperly handles user-supplied input that controls server-side HTTP requests. An attacker can exploit this flaw remotely without requiring authentication or user interaction, by manipulating the input parameters to coerce the server into making arbitrary HTTP requests. This can lead to unauthorized internal network scanning, access to sensitive internal resources, or interaction with external malicious endpoints, potentially facilitating further attacks such as data exfiltration or pivoting within the network. The vulnerability has a CVSS 4.0 score of 5.3, reflecting medium severity due to its network attack vector, low attack complexity, and lack of required privileges or user interaction, but limited impact on confidentiality, integrity, and availability. The vendor has acknowledged the vulnerability and is preparing a fix in version 1.7.8. No known exploits have been reported in the wild yet, but public disclosure increases the urgency for remediation. This vulnerability highlights the importance of validating and sanitizing inputs that influence server-side requests to prevent SSRF attacks.

The SSRF vulnerability in EyouCMS can have significant impacts on organizations using the affected versions. Attackers can leverage this flaw to perform unauthorized internal network reconnaissance, potentially accessing sensitive internal services that are not exposed externally. This can lead to information disclosure, such as accessing internal APIs, metadata services, or administrative interfaces. Additionally, SSRF can be a stepping stone for further exploitation, including lateral movement within the network or launching attacks against other internal systems. While the direct impact on data integrity or availability is limited, the ability to reach otherwise inaccessible resources poses a substantial security risk. Organizations hosting sensitive data or critical infrastructure behind EyouCMS installations are particularly at risk. The medium CVSS score reflects the moderate but non-trivial risk, especially given the ease of remote exploitation without authentication. Failure to address this vulnerability could result in data breaches, compliance violations, and reputational damage.

To mitigate CVE-2025-15373, organizations should promptly upgrade EyouCMS to version 1.7.8 once it is released, as this will contain the official patch addressing the SSRF vulnerability. Until the patch is applied, administrators should consider implementing network-level controls such as firewall rules to restrict outbound HTTP requests from the web server hosting EyouCMS, limiting the server's ability to reach internal or sensitive endpoints. Additionally, input validation and sanitization should be reviewed and enhanced in the saveRemote function or equivalent code paths to ensure that user-supplied URLs are strictly validated against an allowlist of trusted domains or IP addresses. Employing web application firewalls (WAFs) with SSRF detection rules can provide temporary protection by blocking suspicious request patterns. Monitoring logs for unusual outbound requests originating from the EyouCMS server can help detect exploitation attempts early. Finally, conducting a thorough internal network segmentation review to minimize the exposure of critical services to the CMS server will reduce the potential impact of SSRF exploitation.