CVE-2017-0191 in Windows
Summary
by MITRE
A denial of service vulnerability exists in the way that Windows 7, Windows 8.1, Windows 10, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2, and Windows Server 2016 handles objects in memory. An attacker who successfully exploited the vulnerability could cause a target system to stop responding, aka "Windows Denial of Service Vulnerability."
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Analysis
by VulDB Data Team • 12/23/2024
The vulnerability identified as CVE-2017-0191 represents a critical denial of service flaw affecting multiple versions of the Windows operating system including Windows 7, 8.1, 10, and various server editions. This vulnerability manifests in the manner Windows handles memory objects during normal operation, creating a condition where malicious input can trigger system instability. The flaw specifically impacts the Windows scripting engine and related components that process structured storage files, making it particularly dangerous in enterprise environments where system availability is paramount. The vulnerability operates at a fundamental level within the Windows kernel, affecting how memory is allocated, managed, and released during file processing operations.
Technical exploitation of this vulnerability occurs when a specially crafted file is processed by Windows components that utilize the structured storage format. The flaw stems from improper validation of file headers and metadata within compound document structures, which are commonly used in office documents, web pages, and various file types that Windows interprets. When Windows attempts to parse these malformed structures, it encounters memory corruption conditions that lead to system crashes or complete system hangs. This behavior aligns with CWE-125, which describes out-of-bounds read vulnerabilities, and CWE-129, concerning insufficient validation of array indices. The vulnerability is particularly insidious because it can be triggered through multiple attack vectors including email attachments, web downloads, and network shares, making it difficult to contain within a single defensive perimeter.
The operational impact of CVE-2017-0191 extends beyond simple system downtime, creating significant business disruption and potential financial losses for affected organizations. Systems experiencing denial of service conditions may become completely unresponsive, requiring manual intervention for recovery, which can result in extended service interruptions. Network administrators face the challenge of identifying compromised systems in real-time since the vulnerability does not necessarily generate obvious error messages or logging entries. From an attacker perspective, this vulnerability provides a low-effort, high-impact method of disrupting operations, potentially enabling lateral movement within networks once initial access is achieved. The vulnerability's presence in multiple Windows versions means that organizations must implement comprehensive patch management strategies across their entire infrastructure, as any single vulnerable system can serve as a gateway for broader network compromise.
Mitigation strategies for CVE-2017-0191 should encompass both immediate defensive measures and long-term architectural improvements. Microsoft released security updates in March 2017 that addressed the vulnerability through enhanced input validation and memory management routines. Organizations should prioritize immediate patch deployment across all affected systems, particularly those with high availability requirements. Network segmentation and application whitelisting can provide additional defense-in-depth measures, preventing unauthorized file processing operations. Security monitoring should include detection of unusual memory usage patterns and system crash events that may indicate exploitation attempts. The vulnerability's characteristics align with ATT&CK technique T1499, which covers network denial of service attacks, and T1059, covering command and scripting interpreter usage. Regular security assessments and penetration testing should verify that systems are properly hardened against this class of vulnerability, while incident response procedures must be updated to address potential exploitation scenarios.