CVE-2012-0452 in Firefox
Summary
by MITRE
Use-after-free vulnerability in Mozilla Firefox 10.x before 10.0.1, Thunderbird 10.x before 10.0.1, and SeaMonkey 2.7 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via vectors that trigger failure of an nsXBLDocumentInfo::ReadPrototypeBindings function call, related to the cycle collector s access to a hash table containing a stale XBL binding.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 03/20/2021
The CVE-2012-0452 vulnerability represents a critical use-after-free flaw affecting Mozilla Firefox 10.x before 10.0.1, Thunderbird 10.x before 10.0.1, and SeaMonkey 2.7 applications. This vulnerability resides within the browser engine's handling of XBL (XML Binding Language) bindings and specifically targets the cycle collector's interaction with hash tables containing stale XBL binding references. The flaw manifests when the nsXBLDocumentInfo::ReadPrototypeBindings function fails to properly manage memory references during the processing of XML bindings, creating conditions where freed memory locations can be accessed after deallocation. The vulnerability operates through a complex interaction between the JavaScript engine's garbage collection mechanisms and the XBL binding system, where the cycle collector attempts to access hash table entries that have already been freed due to improper reference counting or memory management during binding processing.
The technical exploitation of this vulnerability occurs when a malicious web page or email contains carefully crafted XBL bindings that trigger the problematic code path in the cycle collector. When the browser processes such content, the cycle collector attempts to access a hash table entry that has already been deallocated, resulting in a use-after-free condition. This memory corruption can lead to application crashes or potentially allow remote code execution if an attacker can control the memory layout and overwrite critical function pointers or execute code through controlled memory corruption. The vulnerability is particularly dangerous because it can be triggered through web content, making it a significant threat to user security when visiting malicious websites or opening compromised email attachments.
The operational impact of this vulnerability extends beyond simple denial of service scenarios to encompass potential remote code execution capabilities that could compromise entire user systems. Attackers exploiting this vulnerability could gain unauthorized access to victim systems, potentially leading to data theft, system compromise, or further attack propagation within network environments. The vulnerability's presence in multiple Mozilla products including Firefox, Thunderbird, and SeaMonkey creates a broad attack surface affecting millions of users who rely on these applications for web browsing and email services. The cycle collector's role in memory management makes this particularly concerning as it represents a fundamental component of the browser's stability and security architecture.
Security mitigations for CVE-2012-0452 primarily involve immediate patching of affected applications to version 10.0.1 or later, which includes fixes to the nsXBLDocumentInfo::ReadPrototypeBindings function and improved memory management for XBL bindings. System administrators should implement comprehensive patch management procedures to ensure all affected Mozilla products are updated promptly. Additional protective measures include enabling security features such as address space layout randomization, data execution prevention, and content security policies to limit the potential impact of successful exploitation attempts. Organizations should also consider implementing web filtering solutions and email security controls to prevent users from accessing potentially malicious content that could trigger this vulnerability. This vulnerability aligns with CWE-416, which describes use-after-free conditions, and represents a classic example of memory safety issues that can lead to remote code execution through improper memory management practices in complex software systems.