CVE-2004-2401 in IMail Express
Summary
by MITRE
Stack-based buffer overflow in Ipswitch IMail Express Web Messaging before 8.05 might allow remote attackers to execute arbitrary code via an HTML message with long "tag text."
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Analysis
by VulDB Data Team • 07/05/2025
The vulnerability described in CVE-2004-2401 represents a critical stack-based buffer overflow affecting Ipswitch IMail Express Web Messaging software versions prior to 8.05. This flaw exists within the handling of HTML messages, specifically when processing "tag text" elements that exceed predetermined buffer limits. The vulnerability stems from inadequate input validation and bounds checking mechanisms within the application's HTML parsing routines, creating an exploitable condition where maliciously crafted HTML content can overwrite adjacent memory locations on the stack. Such buffer overflow conditions are particularly dangerous because they can be leveraged by remote attackers to execute arbitrary code with the privileges of the affected service, potentially leading to complete system compromise. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, which directly maps to the ATT&CK technique T1059.007 for command and scripting interpreter, as successful exploitation would enable attackers to execute malicious commands through the compromised application. The flaw occurs when the web messaging application processes HTML content containing excessively long tag text parameters, allowing attackers to overflow the allocated stack buffer and overwrite return addresses or other critical stack variables. This type of vulnerability is particularly severe because it requires no local privileges or authentication to exploit, making it accessible to remote attackers on the internet. The impact extends beyond simple code execution to potentially allow attackers to gain full control over the affected server, including access to all email data, user credentials, and potentially use the compromised system as a launch point for further attacks within the network infrastructure. The vulnerability demonstrates poor defensive programming practices where input length validation is insufficient or completely absent, allowing attackers to manipulate memory layout through carefully crafted payloads. The attack vector involves sending a specially formatted HTML message to the vulnerable IMail Express server, where the application's HTML parser fails to properly validate the length of tag text elements, leading to the buffer overflow condition. This vulnerability aligns with ATT&CK technique T1190 for exploitation of remote services, as it exploits a flaw in a web-based messaging service to achieve unauthorized code execution. The lack of proper bounds checking in the HTML message processing component creates a predictable memory corruption scenario that attackers can reliably exploit. Mitigation strategies should include immediate patching to version 8.05 or later, which contains the necessary input validation fixes. Additionally, network segmentation and access controls should be implemented to limit exposure of the vulnerable service to untrusted networks. Input filtering and sanitization measures should be deployed at the network perimeter to detect and block malicious HTML content before it reaches the vulnerable application. System administrators should also implement monitoring for unusual traffic patterns or attempts to exploit known vulnerabilities in web messaging services. The vulnerability serves as a reminder of the importance of secure coding practices and proper input validation, particularly in applications that process untrusted data from external sources. Organizations should conduct regular vulnerability assessments and maintain updated security patches to protect against similar buffer overflow conditions in other software components. The flaw highlights the critical need for defense-in-depth strategies that combine multiple security controls to protect against exploitation of software vulnerabilities in messaging and web applications.