CVE-2005-0892 in smail
Summary
by MITRE
Buffer overflow in smail 3.2.0.120 allows remote attackers or local users to execute arbitrary code via a long string in the MAIL FROM command and possibly other SMTP commands.
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Analysis
by VulDB Data Team • 01/12/2025
The vulnerability identified as CVE-2005-0892 represents a critical buffer overflow flaw within the smail 3.2.0.120 email server implementation. This issue resides in the Simple Mail Transfer Protocol handling mechanism where the software fails to properly validate input lengths when processing the MAIL FROM command and potentially other SMTP commands. The buffer overflow occurs when an attacker supplies an excessively long string that exceeds the allocated memory buffer space, causing adjacent memory to be overwritten and potentially allowing execution of arbitrary code.
This vulnerability operates at the application layer within the SMTP protocol stack and demonstrates a classic buffer overflow pattern that aligns with CWE-121, which specifically addresses stack-based buffer overflow conditions. The flaw enables both remote attackers who can connect to the SMTP service and local users with access to the system to potentially gain unauthorized code execution privileges. The attack vector leverages the fundamental weakness in input validation where the software does not perform adequate bounds checking on user-supplied data before copying it into fixed-length buffers.
The operational impact of this vulnerability is severe as it provides attackers with potential full system compromise capabilities. When successful, the buffer overflow can lead to arbitrary code execution with the privileges of the smail process, which typically runs with elevated system permissions. This allows attackers to install malware, modify system files, create backdoors, or escalate privileges to gain complete control over the affected system. The vulnerability affects systems running smail 3.2.0.120 and potentially other versions within the same software family that share similar input handling mechanisms.
From an adversarial perspective, this vulnerability maps to several ATT&CK techniques including T1059 for command and scripting interpreter usage and T1068 for exploit for privilege escalation. The attack chain typically involves sending maliciously crafted SMTP commands to the vulnerable server, triggering the buffer overflow condition, and subsequently executing attacker-controlled code. Organizations should implement immediate mitigation strategies including applying vendor patches, disabling unnecessary SMTP services, implementing network segmentation, and monitoring for suspicious SMTP traffic patterns. The vulnerability underscores the importance of proper input validation and memory management practices in network services, emphasizing the need for robust software development lifecycle security measures to prevent such critical flaws from reaching production environments.