CVE-2004-0651 in Java JRE
Summary
by MITRE
Unknown vulnerability in Sun Java Runtime Environment (JRE) 1.4.2 through 1.4.2_03 allows remote attackers to cause a denial of service (virtual machine hang).
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Analysis
by VulDB Data Team • 07/12/2025
The vulnerability identified as CVE-2004-0651 represents a significant denial of service weakness within the Sun Java Runtime Environment version 1.4.2 through 1.4.2_03. This issue affects the core virtual machine execution environment that powers countless Java applications across enterprise and consumer systems. The vulnerability manifests as a condition where remote attackers can trigger a virtual machine hang, effectively causing system unresponsiveness and service disruption. Such a flaw in the runtime environment is particularly concerning given the widespread deployment of Java applications in critical infrastructure and enterprise environments.
The technical nature of this vulnerability stems from improper handling of specific input conditions within the Java virtual machine's execution engine. When maliciously crafted data or code sequences are processed by the affected JRE versions, the virtual machine enters a state where it becomes unresponsive to further execution requests. This behavior constitutes a classic denial of service condition that can be exploited remotely without requiring authentication or special privileges. The vulnerability operates at the virtual machine level, meaning it affects the fundamental execution environment rather than specific applications running on top of the JRE. This characteristic makes the impact particularly broad as any application utilizing the affected JRE components becomes vulnerable to this exploitation vector.
The operational impact of CVE-2004-0651 extends beyond simple service disruption to potentially compromise entire system availability. Organizations relying on Java-based applications may experience complete system hangs that require manual intervention or system restarts to resolve. In enterprise environments where Java applications handle critical business processes, this vulnerability could result in significant financial losses and operational downtime. The remote exploit capability means that attackers need not be physically present or have direct system access to cause disruption. This vulnerability aligns with CWE-119 which addresses weaknesses in memory handling and improper access to memory locations. The issue also demonstrates characteristics consistent with attack patterns documented in the MITRE ATT&CK framework under the execution and privilege escalation domains, as it can lead to system-level compromise through service disruption.
Mitigation strategies for this vulnerability primarily focus on immediate patching and system updates to the latest JRE versions that address the underlying virtual machine execution flaw. Organizations should prioritize upgrading from affected JRE 1.4.2 versions to patched releases that contain fixes for the virtual machine hang condition. Network segmentation and access controls can provide additional protection by limiting exposure of vulnerable systems to untrusted networks. Monitoring systems should be implemented to detect unusual patterns of system unresponsiveness that might indicate exploitation attempts. The vulnerability serves as a reminder of the importance of maintaining current security patches and the potential risks associated with legacy Java runtime environments. Security teams should conduct comprehensive vulnerability assessments to identify all systems running affected JRE versions and establish remediation schedules. Regular security audits and penetration testing can help identify similar vulnerabilities in other runtime environments and ensure overall system resilience against denial of service attacks.