CVE-2025-42963 in NetWeaver Application Server for Java
Summary
by MITRE • 07/08/2025
A critical vulnerability in SAP NetWeaver Application server for Java Log Viewer enables authenticated administrator users to exploit unsafe Java object deserialization. Successful exploitation can lead to full operating system compromise, granting attackers complete control over the affected system. This results in a severe impact on the confidentiality, integrity, and availability of the application and host environment.
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Analysis
by VulDB Data Team • 07/11/2025
This vulnerability resides within SAP NetWeaver Application Server for Java Log Viewer component, representing a critical security flaw that directly impacts the integrity and confidentiality of enterprise environments. The issue stems from unsafe Java object deserialization practices that allow authenticated administrator users to manipulate the deserialization process. According to CWE-502, this falls under the category of Deserialization of Untrusted Data, where the application fails to properly validate or sanitize input data during the object reconstruction phase. The vulnerability exists because the system does not implement adequate safeguards to prevent malicious serialized objects from being processed, creating an attack surface that can be exploited by privileged users.
The technical exploitation mechanism leverages the inherent trust placed in administrator accounts within the SAP environment, where legitimate access rights are abused to inject malicious serialized objects into the deserialization pipeline. When the Log Viewer processes these objects, the Java runtime environment reconstructs the malicious objects, potentially executing arbitrary code with the privileges of the affected service account. This attack vector operates at the application layer and can be classified under ATT&CK technique T1555.003 for credentials from password stores, as it exploits legitimate administrative access to escalate privileges. The vulnerability demonstrates a classic path to privilege escalation where authenticated access is transformed into system-level compromise.
The operational impact of this vulnerability extends far beyond simple data theft, as successful exploitation results in complete system compromise that undermines the fundamental security posture of enterprise environments. Attackers can gain full control over the operating system, enabling them to modify system configurations, install backdoors, exfiltrate sensitive data, or disrupt critical business operations. The confidentiality impact is severe as attackers can access all system resources, while integrity is compromised through potential modifications to system files, configuration data, or application logic. Availability is also threatened as attackers can potentially cause system crashes or resource exhaustion through malicious code execution. This vulnerability directly affects the SAP NetWeaver Application Server environment and can lead to cascading effects throughout the enterprise network.
Organizations must implement immediate mitigations including restricting administrative access to the Log Viewer component, applying security patches from SAP as soon as they become available, and implementing network segmentation to limit the blast radius of potential exploitation. The principle of least privilege should be enforced by restricting access to the Log Viewer functionality to only essential administrative personnel. Additionally, monitoring and logging should be enhanced to detect unusual deserialization activities, and network-level controls should be implemented to prevent unauthorized access to the affected components. According to SAP security advisory practices, administrators should also consider disabling the Log Viewer functionality entirely if it is not required for business operations, as this eliminates the attack surface while maintaining operational continuity. Regular security assessments and vulnerability scanning should be conducted to identify similar deserialization vulnerabilities in other components of the SAP ecosystem.