CVE-2004-1520 in IMail
Summary
by MITRE
Stack-based buffer overflow in IPSwitch IMail 8.13 allows remote authenticated users to execute arbitrary code via a long IMAP DELETE command.
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Analysis
by VulDB Data Team • 07/06/2025
The vulnerability identified as CVE-2004-1520 represents a critical stack-based buffer overflow flaw within IPSwitch IMail version 8.13 that specifically affects the IMAP protocol implementation. This vulnerability resides in the email server software's handling of IMAP DELETE commands, where insufficient input validation allows maliciously crafted long strings to overflow the stack buffer and potentially execute arbitrary code on the affected system. The flaw is particularly dangerous because it requires only authenticated access to exploit, meaning that an attacker who has obtained valid credentials can leverage this vulnerability to gain unauthorized control over the mail server.
The technical nature of this vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows data to overwrite adjacent memory locations on the program stack. The attack vector specifically targets the IMAP protocol implementation within the IMail server software, where the DELETE command processing does not properly validate the length of user-supplied input before copying it into a fixed-size buffer. This allows attackers to overwrite return addresses, function pointers, or other critical stack data structures, enabling code execution with the privileges of the IMail service account. The vulnerability demonstrates a classic buffer overflow pattern where the lack of input sanitization creates a path for attackers to manipulate program execution flow.
From an operational impact perspective, this vulnerability presents a significant threat to organizations relying on IPSwitch IMail for their email infrastructure. Successful exploitation could result in complete system compromise, allowing attackers to execute arbitrary commands, access sensitive email data, establish persistent backdoors, or use the compromised server as a launch point for further attacks within the network. The authenticated nature of the exploit means that attackers do not need to perform extensive reconnaissance or credential harvesting, as they only need valid user accounts to begin the attack process. This makes the vulnerability particularly dangerous in environments where email accounts may be compromised through social engineering, weak password policies, or other authentication bypass techniques.
Organizations should implement immediate mitigations including applying the vendor-provided patches released for this vulnerability, which typically involve input validation improvements and buffer size restrictions in the IMAP command processing code. Network segmentation and access control measures should be strengthened to limit the potential impact of credential compromise, while monitoring systems should be enhanced to detect unusual IMAP activity patterns that might indicate exploitation attempts. Security teams should also conduct comprehensive vulnerability assessments to identify all instances of the affected IMail software and ensure proper patch management procedures are in place. The ATT&CK framework categorizes this vulnerability under T1059 for command and scripting interpreter execution, and T1078 for valid accounts, highlighting the post-exploitation capabilities and initial access vectors that attackers can leverage through this specific flaw.