CVE-2012-3961 in Firefox
Summary
by MITRE
Use-after-free vulnerability in the RangeData implementation in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via unspecified vectors.
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Analysis
by VulDB Data Team • 10/22/2024
The CVE-2012-3961 vulnerability represents a critical use-after-free condition within Mozilla Firefox's RangeData implementation, affecting multiple products including Firefox, Thunderbird, and SeaMonkey across several version ranges. This vulnerability falls under the CWE-416 category of Use After Free, which occurs when a program continues to reference memory after it has been freed, creating opportunities for malicious code execution. The flaw exists in the handling of range data structures that are commonly used in web content processing and manipulation, particularly in scenarios involving dynamic memory allocation and deallocation.
The technical exploitation of this vulnerability involves remote attackers who can manipulate the browser's memory management system through unspecified vectors that trigger improper handling of memory references. When the RangeData implementation processes certain web content, it may free memory associated with range objects while still maintaining references to that memory space. This creates a scenario where subsequent operations on the freed memory can be exploited to either execute arbitrary code or cause heap corruption leading to denial of service conditions. The vulnerability is particularly dangerous because it can be triggered through web pages without requiring user interaction beyond normal browsing activities, making it highly exploitable in real-world scenarios.
The operational impact of CVE-2012-3961 extends beyond simple exploitation to encompass significant security risks for end users and organizations. Attackers can leverage this vulnerability to gain remote code execution capabilities on targeted systems, potentially allowing them to install malware, steal sensitive information, or establish persistent access to affected machines. The heap memory corruption aspect means that successful exploitation could lead to system instability, application crashes, or complete system compromise depending on the execution environment and available privileges. Organizations using affected versions of Firefox, Thunderbird, or SeaMonkey face elevated risk of targeted attacks, particularly in environments where these applications are widely used for email and web browsing.
Mitigation strategies for this vulnerability require immediate patching of affected software versions, with administrators prioritizing updates to Firefox 15.0, Thunderbird 15.0, and SeaMonkey 2.12 or later releases. The fix addresses the underlying memory management issue by ensuring proper handling of range data objects and preventing access to freed memory locations. Security teams should also implement network monitoring to detect potential exploitation attempts and consider deploying application whitelisting policies to restrict access to known vulnerable applications. Additionally, users should be educated about the importance of keeping their browser software updated and should avoid visiting untrusted websites that might contain malicious content designed to exploit this vulnerability. The ATT&CK framework categorizes this type of vulnerability under T1059 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation, highlighting the multi-stage nature of attacks that can leverage such memory corruption flaws.