CVE-2006-3224 in Safari
Summary
by MITRE
Apple Safari 2.0.3 (417.9.3) on Mac OS X 10.4.6 allows remote attackers to cause a denial of service (CPU consumption) via Javascript with an infinite for loop. NOTE: it could be argued that this is not a vulnerability, unless it interferes with the operation of the system outside of the scope of Safari itself.
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Analysis
by VulDB Data Team • 07/29/2018
The vulnerability described in CVE-2006-3224 represents a classic denial of service condition affecting Apple Safari version 2.0.3 running on Mac OS X 10.4.6 systems. This issue stems from the browser's JavaScript engine failing to properly handle infinite loop constructs, specifically when a for loop executes without proper termination conditions. The flaw manifests when malicious JavaScript code attempts to consume excessive CPU resources through unbounded iterative operations, effectively causing the browser to become unresponsive or consume disproportionate system resources.
From a technical perspective, this vulnerability demonstrates a failure in JavaScript execution environment bounds checking and resource management within the Safari browser's JavaScript interpreter. The infinite for loop condition creates a continuous execution path that prevents the JavaScript engine from yielding control back to the operating system's scheduler, leading to sustained high CPU utilization. This behavior aligns with CWE-400, which categorizes "Uncontrolled Resource Consumption" as a common weakness affecting software systems. The vulnerability specifically targets the browser's JavaScript engine implementation where proper loop termination validation and resource limiting mechanisms are absent or insufficient.
The operational impact of this vulnerability extends beyond simple browser unresponsiveness to potentially affect overall system performance and user experience. When an attacker successfully injects JavaScript code containing an infinite loop into a Safari session, the affected browser process consumes excessive CPU cycles, which can degrade system performance and potentially impact other running applications. The issue becomes particularly concerning in web environments where users might unknowingly encounter malicious content, as the denial of service condition can persist until the browser process is manually terminated or the system is restarted. This scenario represents a significant concern for enterprise environments where browser stability and resource allocation are critical for maintaining productivity and system integrity.
Security practitioners should consider this vulnerability in the context of broader threat modeling frameworks such as the ATT&CK matrix, where this issue would fall under the "Resource Exhaustion" tactic category. The vulnerability's classification as a denial of service rather than a more severe exploit reflects the specific nature of the flaw - it does not provide direct access to system resources or allow for arbitrary code execution. However, the potential for this condition to be exploited in conjunction with other attack vectors makes it a legitimate security concern that requires attention. Mitigation strategies should include keeping Safari updated to versions that properly handle JavaScript resource consumption, implementing browser security policies that limit script execution time, and deploying network-level protections such as web application firewalls that can detect and block malicious JavaScript patterns. Additionally, system administrators should consider implementing resource monitoring and alerting mechanisms to detect unusual CPU consumption patterns that might indicate exploitation attempts.
The vulnerability highlights the importance of proper bounds checking and resource management in web browser implementations, particularly in JavaScript engines that handle untrusted code from web pages. Modern browser security models have evolved significantly since 2006 to include more robust protection mechanisms against such resource exhaustion attacks, including script execution timeouts, memory limits, and improved garbage collection strategies. The incident serves as a reminder of the critical need for continuous security assessment and updating of browser components to address emerging threats and maintain system stability.