CVE-2009-2536 in Internet Explorer
Summary
by MITRE
Microsoft Internet Explorer 5 through 8 allows remote attackers to cause a denial of service (memory consumption and application crash) via a large integer value for the length property of a Select object, a related issue to CVE-2009-1692.
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Analysis
by VulDB Data Team • 12/04/2024
Microsoft Internet Explorer versions 5 through 8 contained a critical memory management vulnerability that enabled remote attackers to execute denial of service attacks through malformed Select object length properties. This vulnerability specifically targeted the browser's handling of HTML select elements where the length property could be manipulated with excessively large integer values. The flaw originated from insufficient input validation and boundary checking within the browser's JavaScript engine, particularly affecting the Trident rendering engine's implementation of DOM elements. When a malicious webpage attempted to set an extremely large integer value for the length property of a select object, the browser would consume excessive memory resources attempting to allocate storage for the oversized element, ultimately leading to application crashes and system instability. This vulnerability directly relates to CWE-129, which addresses insufficient validation of length parameters, and represents a classic buffer overflow scenario where improper bounds checking allowed memory allocation to spiral out of control. The attack vector required no special privileges and could be executed through standard web browsing activities, making it particularly dangerous in enterprise environments where users might inadvertently visit compromised websites. The vulnerability's impact extended beyond simple service disruption to potentially destabilize the entire browser process, affecting user productivity and system performance. According to ATT&CK framework category T1499, this represents a denial of service technique that targets application stability and availability. The flaw was particularly concerning because it affected multiple versions of Internet Explorer, spanning a significant portion of the browser's lifecycle, and could be exploited through various web-based attack vectors including malicious advertisements, compromised websites, or phishing campaigns. The memory consumption pattern exhibited by this vulnerability followed predictable exploitation patterns where the browser would continuously allocate memory until system resources were exhausted, resulting in complete application failure. This issue highlighted the importance of robust input validation in web browser implementations and demonstrated how seemingly benign DOM manipulation could lead to critical system instability. The vulnerability's remediation required Microsoft to implement proper integer boundary checking and memory allocation limits within the JavaScript engine, preventing excessive memory consumption through malformed input values. Security researchers noted that similar patterns had been observed in other browser implementations, reinforcing the need for comprehensive input validation across all web rendering components to prevent similar exploitation scenarios.