CVE-2018-8175 in Windows
Summary
by MITRE
An denial of service vulnerability exists when Windows NT WEBDAV Minirdr attempts to query a WEBDAV directory, aka "WEBDAV Denial of Service Vulnerability." This affects Windows 10 Servers, Windows 10.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/27/2023
The CVE-2018-8175 vulnerability represents a critical denial of service weakness within the Windows NT WebDAV Mini-Redirector component that operates at the kernel level. This flaw specifically manifests when the Minirdr attempts to query WebDAV directories, creating a scenario where legitimate system operations can be disrupted through carefully crafted malicious requests. The vulnerability affects multiple Windows 10 versions and Windows Server operating systems, making it particularly concerning given the widespread deployment of these platforms in enterprise environments. The issue stems from inadequate input validation and error handling within the WebDAV subsystem, which fails to properly process malformed directory queries that could trigger system instability.
The technical exploitation of this vulnerability occurs through the WebDAV Mini-Redirector driver's handling of directory enumeration requests. When a malicious WebDAV server responds to directory queries with malformed data structures, the Minirdr component does not properly validate the responses before processing them, leading to memory corruption or infinite loop conditions. This behavior aligns with CWE-129, Input Validation, and CWE-125, Out-of-bounds Read, as the system fails to properly validate the boundaries of received data. The vulnerability operates at the kernel level within the Windows file system stack, making it particularly dangerous as it can potentially cause system crashes or restarts without requiring elevated privileges. The attack vector is typically initiated through network-based WebDAV servers that respond to directory enumeration requests with crafted payloads designed to exploit the Minirdr's processing logic.
From an operational standpoint, this vulnerability can have significant impact on enterprise networks where WebDAV services are actively utilized for file sharing and collaboration. The denial of service condition can render file servers unavailable to legitimate users, disrupting business operations and potentially causing cascading effects throughout the organization's file access infrastructure. Attackers can exploit this weakness by setting up malicious WebDAV servers that respond to directory queries in ways that trigger the vulnerable code path, effectively causing the target system to become unresponsive. The vulnerability's impact is particularly severe in environments where users frequently access WebDAV shares or where automated systems depend on continuous file access. According to ATT&CK framework, this vulnerability maps to T1499.004, Endpoint Denial of Service, and T1071.004, Application Layer Protocol, as it leverages WebDAV protocols to achieve system disruption. The exploitability is relatively straightforward, requiring only network access to a WebDAV server that can be configured to respond with malicious data structures.
Mitigation strategies for CVE-2018-8175 should prioritize immediate patching through Microsoft's security updates, which address the underlying validation issues in the WebDAV Minirdr component. Organizations should also implement network segmentation to limit access to WebDAV resources and disable unnecessary WebDAV functionality where possible. Security monitoring should focus on detecting unusual WebDAV traffic patterns or directory enumeration requests that might indicate exploitation attempts. Additionally, implementing network-based firewalls to block WebDAV traffic to untrusted networks can provide an additional layer of protection. The vulnerability highlights the importance of proper input validation in kernel-level components and underscores the need for robust error handling mechanisms. Organizations should also consider disabling WebDAV functionality entirely if it is not required for business operations, as this eliminates the attack surface entirely. Regular security assessments of file sharing infrastructure and monitoring for anomalous system behavior can help detect exploitation attempts before they cause significant disruption to operations.