CVE-2012-1975 in Firefox
Summary
by MITRE
Use-after-free vulnerability in the PresShell::CompleteMove function 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-2012-1975 vulnerability represents a critical use-after-free condition within Mozilla's web browser engine, specifically affecting the PresShell::CompleteMove function that handles document rendering and layout operations. This flaw exists in multiple Mozilla products including Firefox, Thunderbird, and SeaMonkey across their respective version ranges. The vulnerability stems from improper memory management where freed memory blocks are still referenced or accessed by subsequent operations, creating exploitable conditions that can be leveraged by remote attackers. The issue manifests as heap memory corruption, which can result in either arbitrary code execution or denial of service scenarios depending on exploitation circumstances.
The technical implementation of this vulnerability involves the PresShell component which manages the presentation layer of web documents in Mozilla applications. When processing certain document modifications or layout operations, the CompleteMove function fails to properly manage object lifecycles, leading to situations where memory allocated to objects becomes freed but references to those objects persist. This creates a window of opportunity where malicious code can manipulate the freed memory to redirect execution flow or corrupt memory structures. The vulnerability's exploitation potential is significantly enhanced by the fact that it occurs during normal document processing operations, making it accessible through standard web browsing activities without requiring special privileges or user interaction beyond visiting malicious websites.
From an operational impact perspective, this vulnerability presents severe security implications for organizations relying on affected Mozilla products. Attackers can leverage this flaw to execute arbitrary code with the privileges of the affected application, potentially leading to full system compromise. The heap corruption nature means that exploitation can result in unpredictable behavior including application crashes, data corruption, or complete system compromise depending on the memory layout and exploitation technique used. The vulnerability affects both desktop and enterprise versions of the affected products, with the ESR (Extended Support Release) versions being particularly concerning as they are typically used in enterprise environments where security is paramount. Organizations using these vulnerable versions face significant risk of targeted attacks, especially when users visit compromised websites or open malicious email attachments.
Mitigation strategies for CVE-2012-1975 should prioritize immediate patching of all affected versions to prevent exploitation. Organizations should implement comprehensive vulnerability management processes to ensure timely updates across all Mozilla-based applications in their environment. Network-based defenses such as web application firewalls and content filtering systems can provide additional layers of protection by blocking known malicious content. The vulnerability aligns with CWE-416, which describes use-after-free conditions, and represents a common attack vector categorized under ATT&CK technique T1059 for execution through web-based attacks. Regular security assessments and penetration testing should be conducted to verify the effectiveness of implemented mitigations, while security monitoring systems should be configured to detect anomalous behavior patterns that may indicate exploitation attempts. Organizations should also consider implementing browser hardening measures such as disabling unnecessary features, restricting JavaScript execution, and employing sandboxing technologies to limit potential damage from successful exploitation attempts.