CVE-2018-8254 in SharePoint Enterprise Server
Summary
by MITRE
An elevation of privilege vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server, aka "Microsoft SharePoint Elevation of Privilege Vulnerability." This affects Microsoft Project Server, Microsoft SharePoint. This CVE ID is unique from CVE-2018-8252.
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Analysis
by VulDB Data Team • 03/27/2023
The Microsoft SharePoint Server vulnerability identified as CVE-2018-8254 represents a critical elevation of privilege flaw that exploits improper sanitization of web requests within the SharePoint infrastructure. This vulnerability specifically targets how SharePoint Server processes specially crafted web requests, allowing attackers to escalate their privileges from standard user access to elevated administrative rights. The flaw exists in the server-side request handling mechanism where input validation and sanitization procedures fail to adequately filter malicious content, creating a pathway for unauthorized privilege escalation. This issue affects both Microsoft Project Server and Microsoft SharePoint environments, making it particularly concerning given the widespread deployment of these platforms in enterprise environments.
The technical exploitation of this vulnerability stems from the server's insufficient validation of user-supplied input within web requests. When SharePoint Server receives a crafted request containing malicious payloads, the inadequate sanitization process allows attacker-controlled code or parameters to bypass normal security checks. This failure in input validation creates a direct attack vector that can be leveraged by malicious actors to gain higher-level permissions within the SharePoint environment. The vulnerability is classified under CWE-20, which specifically addresses "Improper Input Validation," and aligns with ATT&CK technique T1068, "Exploitation for Privilege Escalation," demonstrating how attackers can exploit server-side flaws to elevate their access rights. The flaw essentially allows an authenticated user to manipulate server-side processing logic to achieve administrative privileges without proper authorization.
The operational impact of CVE-2018-8254 extends beyond simple privilege escalation, as it can enable comprehensive system compromise within affected SharePoint environments. Once an attacker successfully exploits this vulnerability, they can potentially access sensitive organizational data, modify SharePoint configurations, create new user accounts, and manipulate content management systems. The affected Project Server component adds additional risk since project management data often contains sensitive business information, financial details, and strategic planning documents. Organizations utilizing SharePoint for document management, collaboration, and workflow automation face significant exposure, as the compromised system could serve as a foothold for broader network infiltration. The vulnerability's impact is amplified in environments where SharePoint serves as a central hub for enterprise collaboration and data sharing, potentially allowing attackers to pivot to other systems within the network.
Mitigation strategies for CVE-2018-8254 should prioritize immediate patch deployment through Microsoft's security updates, as the vendor released specific fixes addressing the input sanitization flaw. Organizations must also implement additional defensive measures including enhanced web application firewalls, strict input validation policies, and monitoring for anomalous request patterns that could indicate exploitation attempts. Network segmentation and principle of least privilege enforcement can help limit the potential damage from successful exploitation, while regular security audits and penetration testing should be conducted to identify any remaining vulnerabilities. The remediation process should include thorough testing of patches in staging environments before production deployment, as well as comprehensive monitoring of SharePoint server logs for signs of attempted exploitation. Security teams should also consider implementing automated threat detection mechanisms that can identify suspicious web request patterns consistent with this vulnerability's exploitation methodology, aligning with ATT&CK framework's detection recommendations for privilege escalation techniques.