CVE-2002-0151 in Windows
Summary
by MITRE
Buffer overflow in Multiple UNC Provider (MUP) in Microsoft Windows operating systems allows local users to cause a denial of service or possibly gain SYSTEM privileges via a long UNC request.
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Analysis
by VulDB Data Team • 09/22/2025
The vulnerability described in CVE-2002-0151 represents a critical buffer overflow flaw within the Multiple UNC Provider component of Microsoft Windows operating systems. This issue affects the core networking functionality that handles Universal Naming Convention requests, which are essential for accessing network resources across Windows domains. The MUP service acts as a bridge between local system calls and remote network file operations, making it a prime target for exploitation due to its fundamental role in system networking.
The technical nature of this buffer overflow stems from inadequate input validation within the UNC request processing mechanism. When a local user submits a malformed or excessively long UNC request to the MUP service, the system fails to properly bounds-check the input data before copying it into fixed-size memory buffers. This classic programming error allows an attacker to overwrite adjacent memory locations, potentially corrupting critical system structures or executing arbitrary code. The vulnerability specifically manifests in the way the MUP handles network path specifications, where network resource names are processed without sufficient length restrictions.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable privilege escalation to SYSTEM level access. Local users who can submit malicious UNC requests can exploit this flaw to either crash the target system completely or, more dangerously, gain elevated privileges that allow them to execute code with the highest system permissions. This escalation capability transforms what might initially appear as a denial of service vulnerability into a serious security threat that could compromise entire network domains. The vulnerability affects multiple versions of Windows including Windows 2000, Windows XP, and Windows Server 2003, making it particularly concerning given the widespread deployment of these operating systems in enterprise environments.
This vulnerability maps directly to CWE-121, which describes heap-based buffer overflow conditions, and aligns with ATT&CK technique T1068, which covers privilege escalation through local exploitation. The attack vector requires local system access, making it particularly dangerous in environments where users have legitimate access to systems but could potentially be compromised or malicious. Security researchers have noted that the vulnerability can be triggered through various means including malformed network share connections, scripted network access attempts, or through exploitation of other local vulnerabilities that enable privilege escalation. Organizations should implement immediate mitigations including applying Microsoft security patches, implementing network segmentation to limit local access, and monitoring for unusual UNC request patterns that might indicate exploitation attempts.
The broader implications of this vulnerability highlight the critical importance of input validation and memory safety in operating system components that handle network communications. Microsoft's response included releasing security updates that addressed the buffer overflow conditions in the MUP service, but the vulnerability serves as a reminder of how fundamental system components can contain flaws that affect entire operating system families. Network administrators should consider implementing additional security controls such as disabling unnecessary network protocols, enforcing strict access controls for network resources, and maintaining up-to-date security monitoring to detect potential exploitation attempts. The vulnerability also underscores the need for comprehensive security testing of system services that handle external inputs, particularly those that operate with elevated privileges or critical system functions.