CVE-2003-0903 in Data Access Components
Summary
by MITRE
Buffer overflow in a component of Microsoft Data Access Components (MDAC) 2.5 through 2.8 allows remote attackers to execute arbitrary code via a malformed UDP response to a broadcast request.
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Analysis
by VulDB Data Team • 07/20/2025
The vulnerability described in CVE-2003-0903 represents a critical buffer overflow flaw within Microsoft Data Access Components version 2.5 through 2.8 that enables remote code execution through malformed UDP responses. This issue specifically affects the MDAC component that handles network communications and broadcast requests, creating a pathway for attackers to exploit the system remotely without requiring authentication. The vulnerability stems from insufficient input validation within the UDP response processing mechanism, where the system fails to properly sanitize or limit the size of incoming broadcast responses before copying them into fixed-size buffers. This particular flaw aligns with CWE-121, which categorizes buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations, potentially leading to arbitrary code execution. The attack vector leverages the broadcast nature of UDP communications, where malicious actors can craft specially formatted responses to broadcast requests that trigger the vulnerable code path in MDAC.
The technical exploitation of this vulnerability occurs when a client system running affected MDAC versions receives a malformed UDP response to a broadcast request. The system processes this response without proper bounds checking, causing the data to overflow into adjacent memory regions allocated for the buffer. This overflow can overwrite critical memory locations including return addresses, function pointers, or other control data structures, allowing attackers to redirect program execution flow. The vulnerability is particularly dangerous because it operates over UDP, a connectionless protocol that makes detection more difficult and allows for easier exploitation through broadcast mechanisms. The memory corruption can be leveraged to inject and execute malicious code with the privileges of the affected process, typically resulting in system compromise. According to ATT&CK framework, this vulnerability maps to T1203 - Exploitation for Client Execution, where attackers leverage client-side vulnerabilities to execute malicious code on target systems through network-based attacks.
The operational impact of CVE-2003-0903 extends beyond individual system compromise to potentially affect entire network infrastructures where MDAC components are deployed. Organizations running affected systems become vulnerable to remote code execution attacks that could lead to complete system takeover, data exfiltration, and lateral movement within networks. The broadcast nature of the attack means that a single malicious response could potentially affect multiple systems simultaneously, making this vulnerability particularly concerning for enterprise environments. Network administrators face significant challenges in detecting and mitigating this threat since UDP traffic is inherently difficult to monitor and filter effectively. The vulnerability also demonstrates the risks associated with legacy software components that may not receive adequate security updates, as MDAC versions 2.5 through 2.8 were considered outdated by the time this vulnerability was discovered, highlighting the importance of maintaining current software versions and implementing proper patch management processes. Organizations should implement network segmentation, firewall rules to block unnecessary UDP traffic, and ensure all systems are updated with the latest security patches to prevent exploitation of this vulnerability.