CVE-2002-0366 in Windows
Summary
by MITRE
Buffer overflow in Remote Access Service (RAS) phonebook for Windows NT 4.0, 2000, XP, and Routing and Remote Access Server (RRAS) allows local users to execute arbitrary code by modifying the rasphone.pbk file to use a long dial-up entry.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 09/19/2025
The vulnerability described in CVE-2002-0366 represents a critical buffer overflow flaw within the Remote Access Service implementation of Microsoft Windows operating systems. This security weakness specifically affects Windows NT 4.0, Windows 2000, Windows XP, and the Routing and Remote Access Server components. The vulnerability stems from inadequate input validation mechanisms within the RAS phonebook handling functionality, which processes the rasphone.pbk configuration file used for dial-up connection management.
The technical exploitation of this vulnerability occurs through manipulation of the rasphone.pbk file, which stores dial-up connection parameters and phonebook entries. When a local attacker modifies this file to include an excessively long dial-up entry, the buffer overflow condition is triggered during the parsing process. This occurs because the application fails to properly validate the length of input data before copying it into fixed-size memory buffers. The flaw is categorized as a classic stack-based buffer overflow according to CWE-121, where insufficient bounds checking allows attackers to overwrite adjacent memory locations.
The operational impact of this vulnerability is severe, as it enables local users to execute arbitrary code with the privileges of the affected process. Since the RAS service typically runs with elevated privileges, successful exploitation could lead to complete system compromise. Attackers can leverage this vulnerability to gain unauthorized access to system resources, escalate privileges, and potentially establish persistent backdoors. The vulnerability is particularly dangerous because it requires minimal prerequisites for exploitation, as local access is sufficient to modify the phonebook file, making it an attractive target for both insider threats and attackers who have already gained low-privilege access to a system.
This vulnerability aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter, as the exploitation enables arbitrary code execution through manipulated configuration files. The attack surface is further expanded by the fact that the vulnerability affects multiple Windows versions, increasing the potential impact across various deployment environments. Organizations running affected systems face significant risk, as the vulnerability can be exploited through simple file modification techniques without requiring sophisticated attack vectors or network access.
Mitigation strategies for this vulnerability include immediate application of Microsoft security patches and updates, particularly the security rollup packages released to address this specific buffer overflow issue. System administrators should implement strict file permissions on the rasphone.pbk file to prevent unauthorized modification, though this is considered a temporary measure since the vulnerability exists at the application parsing level. Additionally, implementing application whitelisting policies and monitoring for unusual file modification patterns in system directories can help detect potential exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify systems running unpatched versions of the affected software components. The vulnerability demonstrates the importance of proper input validation and bounds checking in security-critical applications, as outlined in the CWE guidelines for buffer overflow prevention and secure coding practices.