CVE-2011-0072 in Firefox
Summary
by MITRE
Unspecified vulnerability in the browser engine in Mozilla Firefox 3.5.x before 3.5.19 and 3.6.x before 3.6.17, Thunderbird before 3.1.10, and SeaMonkey before 2.0.14 allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors, a different vulnerability than CVE-2011-0074, CVE-2011-0075, CVE-2011-0077, and CVE-2011-0078.
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Analysis
by VulDB Data Team • 11/06/2021
This vulnerability affects the browser engine components of major Mozilla products including Firefox, Thunderbird, and SeaMonkey, representing a critical memory corruption issue that could lead to both denial of service conditions and potential remote code execution. The vulnerability exists in versions prior to specific patch releases where Firefox 3.5.x was updated to 3.5.19, Firefox 3.6.x to 3.6.17, Thunderbird to 3.1.10, and SeaMonkey to 2.0.14. The unspecified nature of the attack vectors indicates that multiple code paths within the browser engine could be exploited, making the vulnerability particularly dangerous as attackers could potentially leverage various methods to trigger the memory corruption. This type of vulnerability falls under the category of heap-based buffer overflows or use-after-free conditions that are commonly classified under CWE-125 (Out-of-bounds Read) and CWE-787 (Out-of-bounds Write) in the CWE database, which are fundamental memory safety issues that can lead to arbitrary code execution when properly exploited. The vulnerability's classification as a remote attack vector means that an attacker could exploit it without requiring local access to the target system, making it particularly concerning for web-based attacks where users might inadvertently visit malicious websites. The fact that this vulnerability is separate from other CVEs in the same year indicates it represents a distinct code path or memory management issue within the browser engine's rendering or parsing components, which typically handle HTML, CSS, and JavaScript processing. Such memory corruption vulnerabilities are particularly dangerous because they can be exploited through web content, allowing attackers to craft malicious websites that trigger the vulnerability when users browse to them. The operational impact of this vulnerability extends beyond simple crashes, as the potential for arbitrary code execution means that attackers could gain complete control over affected systems, making it a high-priority security concern for organizations relying on these browser products.
The technical flaw stems from improper memory management within the browser engine's handling of various web content types, particularly in how it processes complex HTML structures or JavaScript code. When processing malformed or specially crafted web content, the browser engine fails to properly validate memory allocations and deallocations, leading to situations where memory is either overwritten or accessed after being freed. This type of memory corruption typically occurs in the rendering engine's parser or layout components where complex web pages are processed and rendered, often involving JavaScript execution contexts that interact with the browser's internal memory structures. The vulnerability's exploitation requires careful crafting of malicious web content that can trigger specific memory corruption patterns, often involving recursive structures or complex object manipulations that cause the browser engine to allocate memory incorrectly. Security researchers have identified that these types of vulnerabilities often manifest in the JavaScript engine's garbage collection mechanisms or in the rendering engine's handling of DOM objects, where improper reference counting or memory deallocation can lead to exploitable conditions. The ATT&CK framework would categorize this vulnerability under T1203 (Exploitation for Client Execution) and potentially T1059 (Command and Scripting Interpreter) if the exploitation leads to code execution, as attackers would need to leverage the memory corruption to inject and execute malicious code on the target system.
Organizations must prioritize immediate patching of all affected versions to prevent exploitation, as the window of opportunity for attackers to exploit this vulnerability is significant given its remote nature and potential for arbitrary code execution. The patching process should include not only the direct affected products but also any systems that might be running older versions of the browser engine components, as these vulnerabilities often affect multiple applications that share underlying libraries. System administrators should implement monitoring for suspicious network traffic patterns that might indicate exploitation attempts, particularly around web browsing activities and the handling of web content. Security teams should also consider implementing web application firewalls or content filtering systems that can detect and block known malicious patterns that could trigger this vulnerability, though such measures are not foolproof as the exact attack vectors remain unspecified. The vulnerability's potential for causing application crashes also makes it a significant concern for availability, as attackers could use it to perform denial of service attacks against targeted systems or services that rely on these browser products. Organizations should also conduct security awareness training for users to recognize potentially malicious web content and avoid visiting untrusted websites, as the remote exploitation capability means that users can be compromised simply by visiting malicious websites without any additional interaction required from the user. The vulnerability's impact on the broader internet ecosystem means that security researchers and vendors should closely monitor for additional related vulnerabilities that might be discovered in the same code base, as memory corruption vulnerabilities often indicate deeper architectural issues that could affect other components of the browser engine.