CVE-1999-1511 in XtraMail
Summary
by MITRE
Buffer overflows in Xtramail 1.11 allow attackers to cause a denial of service (crash) and possibly execute arbitrary commands via (1) a long PASS command in the POP3 service, (2) a long HELO command in the SMTP service, or (3) a long user name in the Control Service.
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Analysis
by VulDB Data Team • 04/19/2026
The vulnerability identified as CVE-1999-1511 represents a critical buffer overflow issue affecting Xtramail 1.11 software, specifically targeting three distinct service components that handle email communication protocols. This vulnerability resides within the fundamental network service implementations that process user authentication and command execution, creating multiple attack vectors that can be exploited to compromise system stability and potentially gain unauthorized access to affected systems. The buffer overflow conditions occur when the software fails to properly validate input lengths before processing user-supplied data, leading to memory corruption that can result in program termination or arbitrary code execution.
The technical flaw manifests in three specific scenarios where Xtramail's services do not adequately enforce bounds checking on user input parameters. When an attacker sends an excessively long PASS command to the POP3 service, the software's buffer handling mechanism cannot accommodate the oversized input, causing memory corruption that typically results in application crash. Similarly, the SMTP service demonstrates the same vulnerability when processing an overly long HELO command, while the Control Service suffers from buffer overflow when handling extended user names. These vulnerabilities fall under the common CWE-121 buffer overflow category, which represents a fundamental weakness in memory management where data written to a buffer exceeds the allocated memory space, potentially overwriting adjacent memory locations.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable remote code execution, making it particularly dangerous for systems running Xtramail 1.11 in production environments. Attackers exploiting these buffer overflows can cause system crashes that disrupt legitimate email services, while the potential for arbitrary code execution means that compromised systems could be used as launching points for further attacks within the network infrastructure. This vulnerability directly maps to several ATT&CK tactics including privilege escalation and execution through the use of buffer overflow exploits to gain unauthorized access to system resources. The attack surface is particularly concerning as these services are typically exposed to untrusted network traffic and require minimal authentication for exploitation.
Mitigation strategies for CVE-1999-1511 should prioritize immediate software updates to versions that address the buffer overflow conditions in all three affected services. Organizations should implement network segmentation to limit exposure of these services to trusted networks only, while also deploying intrusion detection systems that can identify malformed command sequences targeting these specific vulnerabilities. Input validation should be strengthened through the implementation of proper bounds checking and length limitations on all user-supplied parameters, particularly for authentication commands. System administrators should also consider implementing rate limiting and connection throttling mechanisms to prevent rapid exploitation attempts, while maintaining detailed logging of service interactions to detect potential exploitation attempts. The vulnerability demonstrates the critical importance of proper memory management practices and input validation in network services, aligning with industry best practices outlined in security frameworks such as the OWASP Top Ten and NIST cybersecurity guidelines for secure coding practices.