CVE-2009-2469 in Firefox
Summary
by MITRE
Mozilla Firefox before 3.0.12 does not properly handle an SVG element that has a property with a watch function and an __defineSetter__ function, which allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via a crafted document, related to a certain pointer misinterpretation.
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Analysis
by VulDB Data Team • 08/12/2021
The vulnerability described in CVE-2009-2469 represents a critical memory corruption issue affecting Mozilla Firefox versions prior to 3.0.12. This flaw stems from improper handling of specific Scalable Vector Graphics elements within the browser's rendering engine, specifically when these elements contain properties with watch functions and _defineSetter_ functions. The vulnerability manifests through a pointer misinterpretation that occurs during the processing of malformed SVG content, creating conditions that can lead to unpredictable behavior in the browser's memory management system.
The technical implementation of this vulnerability involves the interaction between JavaScript's property descriptor mechanisms and the browser's SVG rendering pipeline. When Firefox encounters an SVG element with a watch function and _defineSetter_ function, the browser's internal pointer handling becomes corrupted due to improper memory layout interpretation. This misinterpretation creates a scenario where memory addresses are incorrectly processed, leading to either heap corruption or stack corruption depending on the specific execution path taken during document parsing. The vulnerability is particularly dangerous because it can be triggered through crafted web documents that leverage legitimate JavaScript object manipulation features while exploiting the interaction between these features and SVG element processing.
From an operational perspective, this vulnerability enables remote attackers to execute denial of service attacks by causing application crashes and memory corruption, which can lead to browser instability and potential system crashes. More concerning is the potential for arbitrary code execution, which would allow attackers to gain control over the victim's system. The attack vector requires the victim to visit a malicious website containing crafted SVG content, making this a classic web-based exploit that leverages the browser's trust model. The vulnerability affects not only the browser's stability but also represents a significant security risk that could be exploited for more sophisticated attacks including privilege escalation or persistent compromise of user systems.
The impact of this vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read errors. Additionally, the attack pattern corresponds to techniques described in the ATT&CK framework under T1203, which covers Exploitation for Client Execution, and T1059, which covers Command and Scripting Interpreter. Organizations affected by this vulnerability should prioritize immediate patching of Firefox installations to version 3.0.12 or later, as this represents the first release that properly addresses the pointer misinterpretation issue. Network administrators should also consider implementing web filtering measures and monitoring for suspicious SVG content until full patch deployment is achieved. The vulnerability demonstrates the importance of proper memory management in browser engines and highlights how seemingly legitimate JavaScript features can be exploited when combined with specific rendering pipeline conditions.