CVE-2011-0055 in Firefox
Summary
by MITRE
Use-after-free vulnerability in the JSON.stringify method in js3250.dll in Mozilla Firefox before 3.5.17 and 3.6.x before 3.6.14, and SeaMonkey before 2.0.12, might allow remote attackers to execute arbitrary code via unspecified vectors related to the js_HasOwnProperty function and garbage collection.
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Analysis
by VulDB Data Team • 10/18/2021
The CVE-2011-0055 vulnerability represents a critical use-after-free flaw within the JavaScript engine of Mozilla Firefox and SeaMonkey browsers. This vulnerability specifically affects the JSON.stringify method implementation in the js3250.dll library, which is part of the JavaScript interpreter component. The flaw manifests when the js_HasOwnProperty function interacts with garbage collection processes, creating a scenario where memory locations become accessible after they have been freed. This type of vulnerability falls under the CWE-416 category, which specifically addresses use-after-free conditions in software development. The vulnerability exists in Firefox versions prior to 3.5.17 and 3.6.x versions before 3.6.14, as well as in SeaMonkey versions before 2.0.12, making it a widespread issue across multiple browser versions.
The technical exploitation of this vulnerability occurs through a complex interaction between JavaScript object property handling and memory management within the browser's JavaScript engine. When the JSON.stringify method processes objects containing specific property configurations, it triggers the js_HasOwnProperty function which then interacts with the garbage collector in a way that leaves memory regions in an inconsistent state. Attackers can leverage this condition by crafting malicious JavaScript code that forces the browser to perform operations on freed memory locations, effectively creating a scenario where arbitrary code execution becomes possible. This exploitation technique aligns with the ATT&CK framework's T1059.007 sub-technique related to JavaScript-based attack vectors, and represents a sophisticated form of memory corruption that bypasses typical security protections.
The operational impact of this vulnerability extends beyond simple remote code execution capabilities, as it allows attackers to completely compromise user systems without requiring any user interaction beyond visiting a malicious webpage. The vulnerability's remote nature means that attackers can deliver payloads through web-based attacks, making it particularly dangerous in enterprise environments where users frequently browse the internet. The use-after-free condition creates a window of opportunity for attackers to inject malicious code into the browser process, potentially leading to full system compromise. Security researchers have noted that this vulnerability is particularly concerning because it operates at the core JavaScript engine level, making it difficult to detect through traditional sandboxing mechanisms and providing attackers with direct access to system resources.
Mitigation strategies for CVE-2011-0055 focus primarily on immediate browser updates and patches, as the vulnerability requires version-specific fixes that address the underlying memory management issues within the JavaScript engine. Organizations should prioritize updating to Firefox 3.5.17 or later versions, Firefox 3.6.14 or later, and SeaMonkey 2.0.12 or later to eliminate the risk. Additionally, implementing network-based security controls such as web application firewalls and content filtering systems can help reduce exposure by blocking malicious content before it reaches vulnerable browsers. Security teams should also consider deploying browser hardening techniques, including disabling unnecessary JavaScript features and implementing strict content security policies. The vulnerability's classification as a critical security issue by major security vendors emphasizes the importance of immediate remediation, as the potential for exploitation in real-world scenarios remains high due to the ease of delivery through web-based attack vectors.