CVE-2006-6605 in MailEnable
Summary
by MITRE
Stack-based buffer overflow in the POP service in MailEnable Standard 1.98 and earlier; Professional 1.84, and 2.35 and earlier; and Enterprise 1.41, and 2.35 and earlier before ME-10026 allows remote attackers to execute arbitrary code via a long argument to the PASS command.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 07/12/2019
The vulnerability described in CVE-2006-6605 represents a critical stack-based buffer overflow affecting MailEnable email server software across multiple product versions. This flaw exists within the Post Office Protocol (POP) service implementation, specifically when processing the PASS command which is used for user authentication. The vulnerability affects MailEnable Standard versions 1.98 and earlier, Professional versions 1.84 and 2.35 and earlier, and Enterprise versions 1.41 and 2.35 and earlier, before the ME-10026 patch was applied. The buffer overflow occurs when a remote attacker sends a maliciously crafted argument to the PASS command, exploiting a lack of proper input validation and bounds checking in the stack memory allocation.
The technical exploitation of this vulnerability leverages the fundamental principle of stack memory corruption where an attacker can overwrite adjacent memory locations by providing input that exceeds the allocated buffer size. In this case, the PASS command parameter handling does not properly validate the length of user-provided credentials, allowing an attacker to inject excessive data that overflows the stack buffer. This overflow can potentially overwrite return addresses, function pointers, and other critical stack data, enabling arbitrary code execution with the privileges of the POP service process. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which specifically addresses buffer overflows occurring in stack memory regions where insufficient bounds checking allows data to overwrite adjacent memory locations.
The operational impact of this vulnerability is severe as it provides remote attackers with the capability to execute arbitrary code on affected systems without requiring authentication. This means that an attacker could potentially gain full control over the email server, access sensitive email data, modify email content, or establish persistent backdoors. The vulnerability affects organizations running MailEnable services in production environments, making it particularly dangerous as it can be exploited by anyone with network access to the POP service port. The attack surface is broad since POP services are commonly exposed to the internet for email retrieval, and the vulnerability affects multiple versions across different MailEnable product lines, increasing the potential impact across various deployment scenarios.
Organizations should immediately implement mitigations including applying the ME-10026 patch released by MailEnable to address this specific vulnerability. Network segmentation and firewall rules should be implemented to restrict access to POP service ports, limiting exposure to trusted networks only. Additional defensive measures include implementing intrusion detection systems to monitor for suspicious PASS command patterns and conducting regular security assessments of email infrastructure. The vulnerability demonstrates the importance of input validation and proper bounds checking in network services, aligning with ATT&CK technique T1059.007 for command and scripting interpreter. System administrators should also consider implementing application whitelisting policies and monitoring for unusual process execution patterns that could indicate exploitation attempts. Regular security updates and vulnerability assessments are essential to prevent similar issues in other network services and maintain overall system security posture.