CVE-2004-1503 in JRE
Summary
by MITRE
Integer overflow in the InitialDirContext in Java Runtime Environment (JRE) 1.4.2, 1.5.0 and possibly other versions allows remote attackers to cause a denial of service (Java exception and failed DNS requests) via a large number of DNS requests, which causes the xid variable to wrap around and become negative.
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Analysis
by VulDB Data Team • 06/22/2018
The vulnerability described in CVE-2004-1503 represents a critical integer overflow flaw within the Java Runtime Environment's InitialDirContext implementation. This issue affects JRE versions 1.4.2 and 1.5.0, with potential implications for other versions in the same release cycle. The vulnerability stems from improper handling of DNS request counters within the directory context implementation, creating a condition where the system becomes susceptible to denial of service attacks through carefully crafted network traffic patterns.
The technical exploitation of this vulnerability occurs when an attacker sends a large number of DNS requests to a vulnerable Java application. The underlying flaw manifests in the xid variable which serves as a transaction identifier for DNS queries within the InitialDirContext. When the number of requests exceeds the maximum value that can be represented by the integer data type, the variable undergoes integer wraparound, transitioning from its maximum positive value to a negative value. This mathematical overflow creates a condition where the system's DNS handling mechanism becomes corrupted, leading to Java exceptions and failed DNS resolution attempts.
The operational impact of this vulnerability extends beyond simple service disruption, as it fundamentally compromises the reliability of directory services within Java applications. When the xid variable wraps around to negative values, the DNS request processing logic becomes unpredictable and fails to properly handle subsequent requests. This creates a cascading failure effect where legitimate DNS queries cannot be processed correctly, resulting in application instability and complete denial of service for directory-based services. The vulnerability is particularly dangerous because it can be triggered remotely without requiring authentication or special privileges, making it an attractive target for automated attack tools.
From a cybersecurity perspective, this vulnerability aligns with CWE-191, Integer Underflow/Overflow, which specifically addresses issues where integer operations produce results outside the range of the data type. The attack vector follows patterns consistent with the ATT&CK framework's denial of service techniques, specifically targeting application-level vulnerabilities that can be exploited to disrupt service availability. The vulnerability demonstrates how seemingly benign operations like DNS resolution can become attack vectors when proper input validation and integer boundary checking are absent from the implementation.
The recommended mitigation strategies for this vulnerability include immediate application of Oracle's security patches and updates to affected JRE versions, as well as implementing network-level controls to limit the rate of DNS requests to vulnerable applications. Organizations should also consider implementing monitoring solutions to detect unusual DNS request patterns that may indicate exploitation attempts. Additionally, application developers should review their code for similar integer overflow vulnerabilities and implement proper bounds checking for all integer operations, particularly those involving counters and sequence numbers. The vulnerability serves as a reminder of the critical importance of input validation and proper integer handling in security-critical applications, as even minor implementation flaws can result in significant service disruption and availability compromise.