CVE-2018-2476 in NetWeaver
Summary
by MITRE
Due to insufficient URL Validation in forums in SAP NetWeaver versions 7.30, 7.31, 7.40, an attacker can redirect users to a malicious site.
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Analysis
by VulDB Data Team • 04/12/2020
SAP NetWeaver forums suffer from inadequate URL validation mechanisms that create a critical security vulnerability allowing attackers to perform unauthorized redirections to malicious websites. This vulnerability affects multiple versions including 7.30, 7.31, and 7.40, indicating a widespread issue within the platform's authentication and navigation systems. The flaw resides in the forum component's failure to properly validate user input when processing URLs, creating an environment where malicious actors can exploit this weakness to manipulate user navigation behavior. The vulnerability specifically targets the forum functionality where users might encounter links or navigation elements that should be restricted or validated before execution.
The technical implementation of this vulnerability stems from insufficient input validation processes within the forum's URL handling mechanisms. When users interact with forum content, particularly when clicking on links or navigating through discussion threads, the system fails to properly sanitize or validate the destination URLs. This weakness allows attackers to craft malicious URLs that bypass normal validation checks and redirect unsuspecting users to phishing sites, malware distribution platforms, or other harmful destinations. The flaw operates at the application layer and represents a classic case of insecure input handling that enables redirection attacks.
The operational impact of this vulnerability extends beyond simple phishing attempts and can result in significant security breaches within SAP NetWeaver environments. Users who access compromised forums may unknowingly navigate to malicious sites that can harvest credentials, deploy malware, or conduct further social engineering attacks against the organization. The vulnerability is particularly dangerous because it leverages legitimate forum functionality to deliver malicious payloads, making detection more difficult for security monitoring systems. Attackers can exploit this weakness to compromise user sessions, steal sensitive information, or establish footholds within the network infrastructure.
Organizations utilizing affected SAP NetWeaver versions should implement immediate mitigations including patching the identified vulnerability through official SAP security updates. The recommended approach involves applying the appropriate SAP notes and security patches that address the URL validation deficiencies in the forum components. Network administrators should also consider implementing additional security controls such as web application firewalls that can monitor and filter suspicious URL patterns. The vulnerability aligns with CWE-601 and CWE-20 categories, specifically addressing insecure redirection vulnerabilities and input validation failures. From an ATT&CK framework perspective, this weakness maps to techniques involving initial access through malicious links and credential harvesting, making it a significant concern for enterprise security teams. Organizations should also conduct thorough security assessments of their forum configurations and implement proper URL sanitization processes to prevent similar vulnerabilities from emerging in other components of their SAP infrastructure.