CVE-2018-2452 in NetWeaver AS JAVA
Summary
by MITRE
The logon application of SAP NetWeaver AS Java 7.10 to 7.11, 7.20, 7.30, 7.31, 7.40, 7.50 does not sufficiently encode user-controlled inputs, resulting in a cross-site scripting (XSS) vulnerability.
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Analysis
by VulDB Data Team • 03/22/2020
The vulnerability identified as CVE-2018-2452 affects the logon application within SAP NetWeaver AS Java versions ranging from 7.10 through 7.50, representing a critical cross-site scripting flaw that exploits insufficient input validation and encoding mechanisms. This vulnerability resides within the authentication interface of the SAP NetWeaver application server, specifically targeting the logon application component that handles user authentication requests. The flaw enables malicious actors to inject malicious scripts into the application's response, potentially compromising user sessions and system integrity.
The technical implementation of this vulnerability stems from inadequate sanitization of user-supplied data within the logon process. When users submit credentials or other input parameters through the login interface, the application fails to properly encode or escape special characters in the input fields before processing or displaying them in subsequent responses. This oversight creates an environment where attackers can craft malicious payloads containing script tags or other XSS vectors that execute within the victim's browser context. The vulnerability manifests when user-controlled data flows through the application's input handling mechanisms without proper validation or encoding, allowing attackers to inject malicious JavaScript code that persists in the application's response.
The operational impact of CVE-2018-2452 extends beyond simple script execution, as it enables sophisticated attack vectors that can compromise user sessions and potentially escalate privileges within the SAP environment. Attackers can leverage this vulnerability to steal session cookies, perform unauthorized actions on behalf of authenticated users, or redirect victims to malicious websites. The vulnerability affects the core authentication functionality, making it particularly dangerous as it can be exploited by attackers without requiring prior authentication access to the system. This creates a significant risk for organizations relying on SAP NetWeaver AS Java for business-critical applications, as successful exploitation could lead to complete system compromise or data breaches.
Organizations should implement immediate mitigations including input validation and output encoding controls to prevent the injection of malicious scripts into the logon application. The recommended approach involves implementing proper HTML encoding for all user-supplied input before displaying it within the application's response, ensuring that special characters such as angle brackets, quotes, and other potentially dangerous symbols are properly escaped. Additionally, organizations should consider implementing Content Security Policy (CSP) headers to limit the execution of inline scripts and restrict the sources from which scripts can be loaded. SAP has released patches and updates addressing this vulnerability in affected versions, and organizations should prioritize applying these security fixes to their SAP NetWeaver AS Java installations. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and represents a clear violation of secure coding practices that should be addressed through comprehensive input validation and output encoding mechanisms.
This vulnerability demonstrates the critical importance of implementing proper security controls within authentication systems, as the logon application serves as the primary entry point for user access to enterprise applications. The impact of such flaws extends beyond immediate script execution to potential privilege escalation and session hijacking attacks, making it essential for organizations to conduct regular security assessments of their SAP environments. The presence of this vulnerability in multiple versions of SAP NetWeaver AS Java indicates a systemic issue that requires comprehensive remediation rather than isolated patching, emphasizing the need for robust security practices throughout the application lifecycle. Organizations should also consider implementing web application firewalls and monitoring solutions to detect and prevent exploitation attempts targeting this and similar vulnerabilities within their SAP infrastructure.