CVE-2011-2983 in Firefox
Summary
by MITRE
Mozilla Firefox before 3.6.20, Thunderbird 2.x and 3.x before 3.1.12, SeaMonkey 1.x and 2.x, and possibly other products does not properly handle the RegExp.input property, which allows remote attackers to bypass the Same Origin Policy and read data from a different domain via a crafted web site, possibly related to a use-after-free.
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Analysis
by VulDB Data Team • 12/08/2024
The vulnerability described in CVE-2011-2983 represents a critical security flaw in Mozilla's browser and email client software that undermines fundamental web security mechanisms. This issue affects multiple Mozilla products including Firefox versions prior to 3.6.20, Thunderbird versions 2.x and 3.x prior to 3.1.12, and various SeaMonkey versions. The core problem lies in the improper handling of the RegExp.input property, which is a JavaScript feature designed to store the string being matched by regular expressions. This flaw creates a pathway for malicious actors to exploit cross-origin data access restrictions that are fundamental to web security architecture.
The technical implementation of this vulnerability stems from a use-after-free condition within the JavaScript engine's handling of regular expression objects. When the RegExp.input property is manipulated in specific ways, it can cause memory that has been freed to be accessed again, leading to unpredictable behavior. This memory corruption allows attackers to craft malicious web pages that can manipulate the JavaScript engine's internal state, effectively bypassing the Same Origin Policy that normally prevents web pages from accessing data from different domains. The use-after-free condition creates a situation where an attacker can control the memory layout and potentially execute arbitrary code or access sensitive data from other origins.
The operational impact of this vulnerability extends beyond simple data theft, as it represents a complete breakdown of web browser security boundaries. Attackers can leverage this flaw to access cookies, session information, and other sensitive data from different domains without proper authorization. This capability enables sophisticated attacks including session hijacking, credential theft, and cross-site request forgery operations. The vulnerability is particularly dangerous because it operates at the core JavaScript engine level, making it difficult to detect and prevent through traditional web application security measures. The attack surface is broad since it affects multiple Mozilla products and can be triggered through standard web browsing activities.
Security researchers have classified this vulnerability under CWE-416, which specifically addresses use-after-free conditions in memory management, and it aligns with ATT&CK techniques related to privilege escalation and credential access. The remediation strategy requires immediate patching of affected software versions, with Mozilla releasing updates that address the memory management issues in the JavaScript engine. Organizations should prioritize updating all affected Mozilla products to their latest secure versions, as the vulnerability can be exploited through standard web browsing without user interaction. Additionally, network administrators should implement monitoring for suspicious JavaScript behavior and consider implementing additional security layers such as content security policies to limit the potential impact of such exploits. The vulnerability highlights the importance of proper memory management in browser engines and demonstrates how seemingly minor implementation flaws can create significant security risks that undermine fundamental web security models.