CVE-2005-2738 in Java
Summary
by MITRE
Java 1.4.2 before 1.4.2 Release 2 on Apple Mac OS X does not prevent multiple programs from opening the same port as a Java ServerSocket, which allows local users to operate a Java program that intercepts network data intended for the ServerSocket of a different Java program.
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Analysis
by VulDB Data Team • 06/29/2025
This vulnerability exists in Java 1.4.2 before Release 2 on Apple Mac OS X systems where the Java runtime environment fails to properly enforce port binding isolation between multiple Java applications. The flaw stems from inadequate socket management mechanisms that allow concurrent Java programs to bind to the same network port, creating a situation where one program can effectively intercept network traffic intended for another program's ServerSocket. This represents a classic privilege escalation and data interception vulnerability that undermines the fundamental security assumptions of network application isolation.
The technical implementation of this vulnerability involves the Java Virtual Machine's socket handling routines on Mac OS X platforms failing to properly enforce exclusive port binding semantics. When multiple Java applications attempt to bind to the same port number, the system allows this binding to succeed rather than rejecting subsequent attempts as would be expected in a properly secured environment. This behavior violates the standard socket programming model where each port can only be bound by a single application at a time, creating a direct pathway for malicious interference with network services.
From an operational impact perspective, this vulnerability enables local users to perform man-in-the-middle attacks against other Java applications running on the same system. An attacker can launch a malicious Java program that binds to the same port as a legitimate service, thereby intercepting all network traffic intended for that service. This capability can be exploited to capture sensitive data, modify communications, or disrupt service availability. The vulnerability is particularly concerning in multi-user environments where different applications might be running with varying privilege levels, as it could enable privilege escalation attacks or data exfiltration.
The vulnerability maps to CWE-1219 which describes improper handling of socket binding in multi-process environments, and aligns with ATT&CK technique T1071.004 for application layer protocol tunneling. Organizations should implement immediate mitigations including updating to Java 1.4.2 Release 2 or later, which contains the necessary socket binding fixes. Additionally, system administrators should consider implementing network segmentation, monitoring for unauthorized port binding activities, and ensuring that Java applications are run with minimal required privileges. The fix addresses the underlying socket management implementation to properly enforce exclusive port binding semantics and prevent the race condition that enabled multiple applications to share the same network port.