CVE-2025-42926 is a vulnerability identified in SAP NetWeaver Application Server Java, specifically affecting the WD-RUNTIME 7.50 version. The root cause of this vulnerability is a missing authentication check (CWE-306) when accessing certain internal files within the web application. This means that an unauthenticated attacker can directly request and retrieve internal files without any authentication barrier. These files may contain sensitive information about the system, which could aid an attacker in further reconnaissance or targeted attacks. The vulnerability does not allow modification of data or disruption of services, as it does not impact integrity or availability. The CVSS v3.1 base score is 5.3, indicating a medium severity level, with the vector showing network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), low confidentiality impact (C:L), and no impact on integrity or availability (I:N/A:N). No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability is significant because SAP NetWeaver Application Server Java is widely used in enterprise environments to run critical business applications, and unauthorized access to internal files could expose configuration details, system information, or other sensitive data that could facilitate further attacks or data breaches.

For European organizations, the impact of CVE-2025-42926 is primarily related to information disclosure. While the confidentiality impact is rated low, the exposure of internal files could provide attackers with valuable intelligence about the SAP environment, potentially enabling more sophisticated attacks such as privilege escalation, lateral movement, or targeted exploitation of other vulnerabilities. Given SAP's extensive use in European enterprises across sectors like manufacturing, finance, utilities, and public administration, unauthorized access to internal SAP files could undermine trust and compliance with data protection regulations such as GDPR. Although the vulnerability does not directly affect system integrity or availability, the indirect consequences of information leakage could lead to reputational damage, regulatory scrutiny, and increased risk of subsequent attacks. The lack of authentication requirement and the ability to exploit remotely without user interaction increase the risk profile, especially in environments where SAP NetWeaver Application Server Java is exposed to external networks or insufficiently segmented internal networks.

To mitigate CVE-2025-42926, European organizations should take the following specific actions: 1) Immediately review and restrict network exposure of SAP NetWeaver Application Server Java instances, ensuring they are not directly accessible from untrusted networks or the internet. 2) Implement strict access controls and network segmentation to limit access to SAP servers only to authorized users and systems. 3) Monitor and audit access logs for unusual or unauthorized attempts to access internal files within the SAP web application. 4) Apply any available SAP security patches or updates as soon as they are released; if no patch is currently available, engage with SAP support for recommended workarounds or configuration changes to enforce authentication checks. 5) Conduct a thorough security assessment of SAP environments to identify and remediate other potential misconfigurations or vulnerabilities. 6) Employ Web Application Firewalls (WAFs) with custom rules to detect and block unauthorized requests targeting internal files. 7) Educate SAP administrators and security teams about this vulnerability to ensure rapid detection and response to exploitation attempts. These measures go beyond generic advice by focusing on network-level protections, monitoring, and proactive engagement with SAP support.