CVE-2006-2218 in Internet Explorer
Summary
by MITRE
Unspecified vulnerability in Internet Explorer 6.0 on Microsoft Windows XP SP2 allows remote attackers to execute arbitrary code via "exceptional conditions" that trigger memory corruption, as demonstrated using an exception handler and nested object tags, a variant of CVE-2006-1992.
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Analysis
by VulDB Data Team • 06/22/2025
This vulnerability represents a critical memory corruption flaw in Microsoft Internet Explorer 6.0 running on Windows XP Service Pack 2 systems. The issue manifests through exceptional conditions that occur during the processing of web content, specifically when handling nested object tags in conjunction with exception handlers. The vulnerability falls under the category of heap corruption and memory management flaws, which are commonly classified as CWE-121 heap-based buffer overflow or CWE-787 out-of-bounds write. Attackers can exploit this weakness by crafting malicious web pages that trigger specific exception handling scenarios, causing the browser to write data beyond allocated memory boundaries. The exploitation technique leverages the interaction between JavaScript exception handling mechanisms and nested object tag structures, creating a condition where memory corruption occurs during the normal execution flow of the browser's rendering engine. This particular variant demonstrates how seemingly benign browser functionality can be manipulated to achieve arbitrary code execution, representing a sophisticated attack vector that bypasses standard security mechanisms. The vulnerability is particularly dangerous because it operates within the browser's core rendering and exception handling subsystems, making it difficult to detect and prevent through traditional security measures. The attack requires a victim to visit a malicious website that contains specially crafted HTML and JavaScript code designed to trigger the memory corruption condition.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with complete control over the affected system. Once successfully exploited, attackers can execute malicious code with the privileges of the user running Internet Explorer, potentially leading to full system compromise and persistence mechanisms. The vulnerability's exploitation requires user interaction through web browsing, making it particularly effective in phishing campaigns or drive-by download scenarios. Security researchers have noted that this type of memory corruption vulnerability often serves as a foundation for more advanced attacks, as it can be chained with other exploits to bypass modern security features such as address space layout randomization and data execution prevention. The specific conditions that trigger this vulnerability involve the interaction between the browser's JavaScript engine and its object model handling, particularly when processing nested HTML elements within exception contexts. This exploitation pattern aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1068 for exploit for privilege escalation, as the initial code execution can be leveraged to gain higher system privileges. The vulnerability demonstrates the inherent complexity of modern web browsers and their susceptibility to memory corruption issues that arise from complex interactions between multiple subsystems. Microsoft's patch for this vulnerability addressed the underlying memory management issues in the browser's object handling and exception processing mechanisms, though the exploitation techniques remain relevant for understanding browser security architectures.
Mitigation strategies for this vulnerability involve multiple layers of defense to protect against both the specific exploitation techniques and similar memory corruption issues. System administrators should prioritize immediate patch deployment for the affected Microsoft Internet Explorer versions, as this vulnerability has been widely exploited in the wild. Browser isolation techniques and sandboxing mechanisms can help contain potential exploitation attempts, though the vulnerability's nature makes complete protection challenging. Network-based security controls such as web application firewalls and content filtering systems can help detect and block malicious web content before it reaches vulnerable systems. The vulnerability highlights the importance of keeping browser software updated and implementing secure browsing practices, including disabling unnecessary browser features and maintaining strict access controls. Security monitoring should focus on detecting anomalous browser behavior and unusual memory access patterns that might indicate exploitation attempts. Organizations should also consider implementing browser hardening measures such as disabling ActiveX controls, restricting JavaScript execution, and using secure browsing configurations that limit the attack surface. The vulnerability serves as a reminder of the critical importance of memory safety in software development and the need for comprehensive security testing, particularly in complex applications like web browsers that handle untrusted content from multiple sources. Regular security assessments and penetration testing should include evaluation of browser memory corruption vulnerabilities to ensure adequate protection against similar threats.