CVE-2018-8650 in SharePoint Enterprise Server
Summary
by MITRE
A cross-site-scripting (XSS) vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server, aka "Microsoft Office SharePoint XSS Vulnerability." This affects Microsoft SharePoint.
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Analysis
by VulDB Data Team • 02/28/2025
The vulnerability identified as CVE-2018-8650 represents a critical cross-site scripting flaw within Microsoft SharePoint Server that stems from inadequate input validation and sanitization mechanisms. This weakness allows attackers to inject malicious scripts into web requests that are processed by the SharePoint server, creating a persistent security risk for organizations relying on Microsoft's collaboration platform. The vulnerability specifically manifests when SharePoint Server fails to properly sanitize user-supplied input in web requests, enabling attackers to execute arbitrary code within the context of a victim's browser session.
The technical exploitation of this vulnerability occurs through the manipulation of web requests sent to SharePoint Server, where malicious payloads are embedded in parameters or content that the server processes without adequate sanitization. This flaw operates at the application layer and leverages the inherent trust relationships within web applications, allowing attackers to bypass standard security controls that would normally prevent script execution. The vulnerability's impact is amplified by SharePoint Server's widespread deployment across enterprise environments, making it an attractive target for threat actors seeking to compromise user sessions and potentially escalate privileges within organizational networks.
From an operational standpoint, the exploitation of CVE-2018-8650 can result in significant security breaches including session hijacking, data exfiltration, and privilege escalation attacks. Attackers can leverage this vulnerability to steal authentication cookies, access sensitive documents, or redirect users to malicious sites that further compromise the security posture of affected organizations. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and maps to ATT&CK technique T1059.008 for script execution through web applications. Organizations with SharePoint Server deployments face substantial risk of unauthorized access and data breaches when this vulnerability remains unpatched.
Mitigation strategies for CVE-2018-8650 should prioritize immediate application of Microsoft security patches and updates to affected SharePoint Server versions. Organizations must implement comprehensive input validation mechanisms and ensure that all user-supplied content is properly sanitized before processing or display within SharePoint environments. Network segmentation and web application firewalls can provide additional protective layers to detect and block malicious requests attempting to exploit this vulnerability. Regular security assessments and penetration testing should be conducted to identify potential exploitation vectors, while security awareness training for administrators can help prevent social engineering attacks that might leverage this vulnerability. The vulnerability's classification as a persistent XSS flaw requires ongoing monitoring and remediation efforts to maintain effective protection against both current and emerging threats targeting SharePoint Server infrastructure.