CVE-2020-1244 in Windows
Summary
by MITRE
A denial of service vulnerability exists when Connected User Experiences and Telemetry Service improperly handles file operations, aka 'Connected User Experiences and Telemetry Service Denial of Service Vulnerability'. This CVE ID is unique from CVE-2020-1120.
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Analysis
by VulDB Data Team • 10/23/2020
The vulnerability described in CVE-2020-1244 represents a critical denial of service weakness within Microsoft's Connected User Experiences and Telemetry Service component. This service operates as part of the Windows operating system's telemetry infrastructure, collecting usage data and system information to improve Microsoft products and services. The flaw manifests when the service processes file operations in an improper manner that can lead to system instability and complete service unavailability. The vulnerability specifically affects how the Connected User Experiences and Telemetry Service handles file system interactions, creating conditions where legitimate system operations can be disrupted through crafted file handling scenarios.
From a technical perspective, this vulnerability falls under CWE-400, which addresses uncontrolled resource consumption, and more specifically relates to improper handling of file operations within system services. The flaw allows attackers to potentially trigger resource exhaustion or malformed file processing that causes the telemetry service to crash or become unresponsive. The service's failure to properly validate or sanitize file operations creates an attack surface where malicious file manipulation can lead to denial of service conditions. This represents a classic example of insufficient input validation and resource management within Windows system services, where the service fails to properly handle edge cases or malformed file operations that should be gracefully managed.
The operational impact of this vulnerability extends beyond simple service disruption to potentially affect system stability and monitoring capabilities. When the Connected User Experiences and Telemetry Service becomes unavailable, it can prevent proper collection of usage data, system performance metrics, and diagnostic information that Microsoft relies on for product improvement and security updates. Organizations may experience difficulties in maintaining accurate system health monitoring and could face challenges in detecting other security incidents due to reduced telemetry capabilities. The vulnerability can be exploited by local or remote attackers to cause persistent service disruption, potentially requiring system restarts or manual service recovery procedures to restore normal operations.
Mitigation strategies for CVE-2020-1244 should focus on implementing proper service hardening and access controls for the Connected User Experiences and Telemetry Service. Microsoft recommends applying the latest security updates and patches to address the vulnerability, which typically involve modifying how file operations are processed within the service. Organizations should consider implementing network segmentation and access controls to limit potential exploitation vectors, while also monitoring for unusual file system activity or service disruptions that could indicate exploitation attempts. The ATT&CK framework categorizes this type of vulnerability under T1489, which covers service stoppage techniques, and T1070, covering indicator removal on host. System administrators should also implement proper monitoring of service availability and telemetry data collection to detect potential exploitation attempts. Additional defensive measures include disabling unnecessary telemetry features where appropriate and maintaining regular system updates to ensure protection against known vulnerabilities in Windows services.