CVE-2000-0544 in Windows
Summary
by MITRE
Windows NT and Windows 2000 hosts allow a remote attacker to cause a denial of service via malformed DCE/RPC SMBwriteX requests that contain an invalid data length.
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Analysis
by VulDB Data Team • 10/13/2025
This vulnerability exists in Microsoft Windows NT and Windows 2000 operating systems where the Server Message Block protocol implementation fails to properly validate data length parameters in DCE/RPC SMBwriteX requests. The flaw occurs when the system receives malformed network packets that contain invalid data length values, causing the system to crash or become unresponsive. This represents a classic buffer overflow condition where insufficient input validation allows an attacker to manipulate memory structures through crafted network traffic. The vulnerability is classified under CWE-125 as an out-of-bounds read condition that can lead to system instability and denial of service. From an operational perspective, this weakness allows remote attackers to execute denial of service attacks against targeted systems without requiring authentication, making it particularly dangerous in networked environments where systems may be directly exposed to external traffic. The attack vector involves sending specially crafted DCE/RPC SMBwriteX requests over the network to the affected Windows systems, which then process these malformed requests and subsequently crash or become unresponsive. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under T1499.004 for network denial of service attacks, where adversaries leverage system weaknesses to disrupt availability of services. The impact extends beyond simple system crashes as it can affect business continuity and availability of critical services that depend on these operating systems. Organizations running these legacy systems face significant risk as the vulnerability affects systems that were designed without robust input validation mechanisms for network protocols. The flaw demonstrates a failure in proper protocol implementation where the system does not adequately sanitize incoming data before processing it, leading to system instability and potential service disruption. This vulnerability type represents a common pattern in legacy operating systems where network protocol handlers were not designed with comprehensive input validation in mind. The attack can be executed remotely without requiring any special privileges or authentication credentials, making it an attractive target for malicious actors seeking to disrupt services. From a security perspective, this vulnerability highlights the importance of proper input validation and the need for robust protocol implementations that can handle malformed data gracefully without crashing the underlying system. The issue affects systems that implement the Server Message Block protocol for file sharing and other network services, making it particularly relevant for enterprise environments that rely on file sharing capabilities. Organizations should consider implementing network segmentation and access controls to limit exposure to this vulnerability, while also planning for system upgrades to more recent operating system versions that have addressed these protocol handling weaknesses. The vulnerability underscores the critical need for regular security assessments and patch management programs that can identify and remediate such protocol-level weaknesses before they can be exploited in real-world attacks.