CVE-2020-6313 in NetWeaver Application Server
Summary
by MITRE
SAP NetWeaver Application Server JAVA(XML Forms) versions 7.30, 7.31, 7.40, 7.50 does not sufficiently encode user controlled inputs, which allows an authenticated User with special roles to store malicious content, that when accessed by a victim, can perform malicious actions by executing JavaScript, leading to Stored Cross-Site Scripting.
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Analysis
by VulDB Data Team • 09/09/2020
SAP NetWeaver Application Server JAVA XML Forms represents a critical web application framework that processes user inputs through XML-based forms and data handling mechanisms. The vulnerability identified as CVE-2020-6313 specifically targets the insufficient input validation and output encoding practices within these XML forms processing components. This flaw exists across multiple versions including 7.30, 7.31, 7.40, and 7.50, indicating a widespread issue affecting the core application server functionality. The vulnerability manifests when user-controlled data enters the system through XML form submissions and is subsequently stored without proper sanitization or encoding measures.
The technical implementation of this vulnerability stems from inadequate HTML encoding of user inputs within the XML forms processing pipeline. When authenticated users with specific administrative privileges submit malicious content through XML forms, the system fails to properly sanitize or encode this data before storing it in the application's database or processing context. This stored content retains its malicious payload and can be executed when other users access the affected pages or data. The vulnerability specifically enables stored cross-site scripting attacks where JavaScript code embedded in XML form inputs gets executed in the victim's browser context, bypassing standard security mechanisms that typically protect against such attacks.
The operational impact of CVE-2020-6313 extends beyond simple data corruption or display issues, as it creates a persistent threat vector that can be exploited by attackers who gain access to accounts with the required special roles. An attacker with sufficient privileges can inject malicious scripts that can steal session cookies, redirect users to phishing sites, modify application behavior, or perform unauthorized actions on behalf of legitimate users. The vulnerability's exploitation requires authentication with specific roles, making it less accessible to casual attackers but still dangerous within compromised environments where attackers have elevated privileges. This stored XSS vulnerability can lead to complete application compromise, data exfiltration, and potential lateral movement within the network infrastructure.
Mitigation strategies for this vulnerability should prioritize immediate patch application from SAP as the primary defense mechanism. Organizations should implement comprehensive input validation and output encoding controls across all XML form processing components, ensuring that all user-supplied data undergoes proper sanitization before storage. Network segmentation and role-based access controls should be reinforced to limit the scope of potential exploitation, while monitoring systems should be enhanced to detect unusual XML form submissions. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and its exploitation patterns correspond to ATT&CK technique T1566 related to credential harvesting through phishing. Regular security assessments and penetration testing should be conducted to identify similar encoding flaws in other application components, while application firewalls and web application security controls should be configured to detect and block malicious script payloads in real-time.