SAP Netweaver JAVA – Log Viewer – Insecure JAVA Deserialization
Impact on Business
Successful exploitation of this vulnerability can fully compromise the SAP system. An authenticated attacker with high privileges could execute arbitrary OS commands, leading to a complete compromise of confidentiality, integrity, and availability of the affected system and its business applications.
Vulnerability Details
The Log Viewer application in SAP NetWeaver JAVA contains a vulnerability related to the insecure deserialization of Java objects. An authenticated attacker with high privileges can exploit the “Connect to Remote System” functionality to connect to a malicious RMI server. This allows the attacker to supply arbitrary serialized Java objects, which, when deserialized by the SAP system, can lead to arbitrary OS command execution as the SAP Administrator (sidadm) user.
Solution
SAP has released SAP Note 3621771 which provides patched versions of the affected components.
The patches can be downloaded from https://me.sap.com/notes/3621771.
Onapsis strongly recommends SAP customers to download the related security fixes and apply them to the affected components in order to reduce business risks.
Report Timeline
- 05/29/2025: Onapsis reports vulnerability to SAP
- 07/08/2025: SAP issues the patch
References
Advisory Information
- Public Release Date: 07/30/2026
- Security Advisory ID: ONAPSIS-2026-0011
- Researcher(s): Cristian Scraba, Pablo Artuso
Vulnerability Information
- Vendor: SAP
- Affected Components: SAP NetWeaver Application Server for Java (Log Viewer) (Check SAP Note 3621771 for detailed information on affected releases)
- Vulnerability Class: CWE-502: Deserialization of Untrusted Data
- CVSS v3 score: 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H)
- Risk Level: Critical
- Assigned CVE: CVE-2025-42963
- Vendor patch Information: SAP Security NOTE 3621771
Affected Components Description
- SAP NetWeaver JAVA – Log Viewer
- Software component: LMNWABASICAPPS
- Development Component: tc~lm~itsam~ui~lv~client_ui
- NW version: 7.5
About our Research Labs
Onapsis Research Labs provides the industry analysis of key security issues that impact mission-critical systems and applications. Delivering frequent and timely security and compliance advisories with associated risk levels, Onapsis Research Labs combine in-depth knowledge and experience to deliver technical and business-context with sound security judgment to the broader information security community.
Find all reported vulnerabilities at: https://github.com/Onapsis/vulnerability_advisories
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