CVE-2013-0081 in SharePoint Server
Summary
by MITRE
Microsoft SharePoint Portal Server 2003 SP3 and SharePoint Server 2007 SP3, 2010 SP1 and SP2, and 2013 do not properly process unassigned workflows, which allows remote attackers to cause a denial of service (W3WP process hang) via a crafted URL, aka "SharePoint Denial of Service Vulnerability."
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Analysis
by VulDB Data Team • 05/24/2021
The vulnerability identified as CVE-2013-0081 represents a critical denial of service weakness in Microsoft SharePoint Server versions including 2003 SP3, 2007 SP3, 2010 SP1 and SP2, and 2013. This flaw specifically manifests when the system processes unassigned workflows within the SharePoint environment, creating a condition where malicious actors can manipulate the workflow engine to trigger system instability. The vulnerability operates through the web application's handling of workflow processes, where the W3WP.exe process becomes unresponsive and enters a state of indefinite hanging, effectively rendering the SharePoint service unavailable to legitimate users. This issue falls under the category of improper input validation and resource management within the application's workflow processing subsystem.
The technical exploitation of this vulnerability occurs when remote attackers craft specific URLs that trigger the processing of unassigned workflows in SharePoint Server. The flaw exists because the system fails to properly validate or handle workflow states that are not assigned to any specific user or process, leading to a condition where the workflow engine attempts to process these orphaned workflows indefinitely. When the W3WP process encounters such malformed workflow requests, it becomes stuck in a loop or waits for resources that never become available, causing the entire web application pool to become unresponsive. This behavior represents a classic denial of service scenario where legitimate system resources are consumed in a manner that prevents normal operation. The vulnerability specifically targets the workflow management component and the underlying web application processing engine, creating a cascading effect that impacts the entire SharePoint service availability.
The operational impact of CVE-2013-0081 extends beyond simple service disruption to potentially compromise business continuity and operational efficiency within organizations relying on SharePoint for collaboration and document management. When the W3WP process hangs, users experience complete service outages, preventing access to SharePoint sites, documents, and workflow processes that are essential for business operations. The vulnerability affects organizations that have not applied the relevant security updates, leaving their SharePoint infrastructure exposed to potential exploitation by attackers who may seek to disrupt business operations or create cover for more sophisticated attacks. This vulnerability particularly impacts organizations with complex workflow processes, as these systems are more likely to encounter unassigned workflows during normal operation, increasing the attack surface and potential impact.
Organizations should implement immediate mitigations including applying the relevant Microsoft security patches that address this vulnerability, specifically the updates released for SharePoint Server 2003 SP3, 2007 SP3, 2010 SP1 and SP2, and 2013. Network segmentation and access control measures can provide additional protection by limiting the ability of external attackers to reach vulnerable SharePoint instances. The vulnerability demonstrates weaknesses in the principle of least privilege and proper input validation, aligning with CWE-20 - Improper Input Validation and CWE-400 - Uncontrolled Resource Consumption. From an attack perspective, this vulnerability corresponds to techniques described in the MITRE ATT&CK framework under the T1499 - Endpoint Denial of Service category, specifically targeting the availability aspect of the CIA triad. Additionally, the vulnerability highlights the importance of proper workflow management and resource cleanup procedures within enterprise collaboration platforms, emphasizing the need for comprehensive security testing and validation of workflow processes in SharePoint environments.