CVE-2005-1987 in Exchange
Summary
by MITRE
Buffer overflow in Collaboration Data Objects (CDO), as used in Microsoft Windows and Microsoft Exchange Server, allows remote attackers to execute arbitrary code when CDOSYS or CDOEX processes an e-mail message with a large header name, as demonstrated using the "Content-Type" string.
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Analysis
by VulDB Data Team • 06/30/2025
The vulnerability identified as CVE-2005-1987 represents a critical buffer overflow flaw within Microsoft Collaboration Data Objects CDOEX and CDOSYS components that form part of the Microsoft Windows operating system and Microsoft Exchange Server email infrastructure. This vulnerability specifically targets the processing of email messages where the header name exceeds the allocated buffer space, creating a condition that can be exploited by remote attackers to execute arbitrary code on affected systems. The flaw manifests when these components encounter email messages containing excessively long header names, particularly demonstrated through manipulation of the "Content-Type" string field.
The technical implementation of this vulnerability stems from inadequate input validation and buffer management within the CDO processing routines. When the system attempts to parse email headers with oversized field names, the buffer allocated for header processing becomes insufficient to accommodate the incoming data. This overflow condition occurs because the CDO components do not properly validate the length of header names before attempting to copy them into fixed-size memory buffers, leading to memory corruption that can be leveraged by malicious actors to overwrite adjacent memory locations and potentially inject executable code.
The operational impact of this vulnerability extends across multiple Microsoft platforms and services, creating a significant security risk for organizations relying on Windows systems and Exchange Server environments. Attackers can exploit this weakness by crafting specially formatted email messages containing oversized header fields that trigger the buffer overflow during normal message processing. The remote execution capability means that attackers do not require local access to the system and can exploit this vulnerability from anywhere on the network, making it particularly dangerous for email servers and client systems. Successful exploitation could result in complete system compromise, allowing attackers to gain unauthorized access, execute malicious code, and potentially establish persistent backdoors within the affected infrastructure.
This vulnerability aligns with CWE-121, which describes the classic stack-based buffer overflow condition, and represents a clear violation of secure coding practices that should prevent buffer overflows through proper input validation and bounds checking. The ATT&CK framework categorizes this type of vulnerability under T1190, known as "Exploit Public-Facing Application," as it represents a remote exploitation vector targeting publicly accessible email services. Organizations should implement immediate mitigations including applying Microsoft security patches, implementing email filtering rules to detect and block suspicious header lengths, and configuring network segmentation to limit exposure of vulnerable systems. Additionally, monitoring for unusual email processing patterns and implementing intrusion detection systems can help identify exploitation attempts before they succeed in compromising system integrity.