CVE-2017-0174 in Windows
Summary
by MITRE
Windows NetBIOS in Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 allows a denial of service vulnerability when it improperly handles NetBIOS packets, aka "Windows NetBIOS Denial of Service Vulnerability".
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 01/07/2021
The vulnerability identified as CVE-2017-0174 represents a critical denial of service flaw within the Windows NetBIOS implementation across multiple operating system versions including Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016. This vulnerability specifically targets the NetBIOS service which operates as a legacy network communication protocol that facilitates name resolution and service discovery in Windows environments. The flaw manifests when the system improperly processes NetBIOS packets, leading to potential system instability and service disruption. According to CWE-121, this vulnerability stems from improper handling of input data within memory operations, creating a condition where malformed NetBIOS packets can trigger unexpected behavior in the system's network stack. The vulnerability aligns with ATT&CK technique T1499.004 which involves network denial of service attacks targeting system resources and network protocols. The impact extends beyond simple service interruption as the flaw can potentially cause system crashes or restarts, affecting availability of critical network services and applications that depend on NetBIOS functionality for name resolution and service discovery.
The technical exploitation of this vulnerability occurs through the transmission of specially crafted NetBIOS packets to a target system running the affected Windows versions. When the system receives these malformed packets, the NetBIOS service fails to properly validate or process the incoming data, leading to memory corruption or buffer overflow conditions that ultimately result in system instability. The vulnerability is particularly concerning because NetBIOS remains active in many Windows environments despite being superseded by more modern protocols such as DNS and SMB. Attackers can leverage this weakness to perform denial of service attacks against networked systems, potentially causing widespread disruption in enterprise environments where legacy NetBIOS functionality is still utilized for backward compatibility. The flaw demonstrates poor input validation practices and inadequate error handling within the Windows networking stack, making it susceptible to exploitation by adversaries who can craft malicious packets to trigger the vulnerable code paths.
From an operational perspective, the vulnerability creates significant risk for organizations maintaining legacy Windows environments or those with extended support for NetBIOS services. Network administrators face potential disruptions to critical services including file sharing, print services, and domain name resolution that depend on NetBIOS functionality. The vulnerability can be exploited remotely without authentication, making it particularly dangerous in networked environments where systems may be exposed to untrusted networks. Organizations with multiple systems running affected Windows versions are at risk of cascading failures if attackers successfully exploit this vulnerability across their network infrastructure. The impact extends to business continuity as system restarts and service restoration can result in significant downtime and productivity loss. Additionally, the vulnerability may be exploited as part of larger attack campaigns where initial access is achieved through other vectors, followed by exploitation of this denial of service vulnerability to maintain persistence or disrupt operations.
Organizations should implement immediate mitigations including applying Microsoft security updates released as part of the patch Tuesday cycle, specifically addressing this vulnerability through the Microsoft Security Bulletin MS17-010. Network segmentation and firewall rules should be configured to restrict unnecessary NetBIOS traffic between network segments, particularly disabling NetBIOS name service on systems that do not require it. System administrators should monitor network traffic for unusual patterns that may indicate exploitation attempts, particularly looking for malformed NetBIOS packets or excessive connection attempts. The implementation of intrusion detection systems with signature-based detection for known NetBIOS attack patterns can provide additional monitoring capabilities. Organizations should also conduct vulnerability assessments to identify systems running legacy NetBIOS services and plan for migration to modern network protocols. Regular security awareness training should emphasize the importance of applying security patches promptly and maintaining up-to-date system configurations to prevent exploitation of known vulnerabilities. The vulnerability serves as a reminder of the critical importance of maintaining secure network configurations and the necessity of keeping legacy protocols properly secured or deprecated in modern network environments.