CVE-2024-9400 in Thunderbird
Summary
by MITRE • 10/01/2024
A potential memory corruption vulnerability could be triggered if an attacker had the ability to trigger an OOM at a specific moment during JIT compilation. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Thunderbird < 128.3, and Thunderbird < 131.
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Analysis
by VulDB Data Team • 03/08/2025
This vulnerability represents a critical memory corruption issue that emerges during just-in-time compilation processes within Mozilla's JavaScript engine. The flaw occurs when an out-of-memory condition is deliberately triggered at a precise moment during JIT compilation, creating a potential pathway for arbitrary code execution. The vulnerability specifically impacts Firefox versions prior to 131, Firefox ESR versions prior to 128.3, Thunderbird versions prior to 128.3, and Thunderbird versions prior to 131, indicating a widespread exposure across Mozilla's browser and email client products. The technical nature of this vulnerability aligns with CWE-122, which describes heap-based buffer overflow conditions, and represents a sophisticated exploitation vector that requires precise timing and memory manipulation.
The operational impact of this vulnerability extends beyond simple memory corruption, as it could enable attackers to execute malicious code with the privileges of the affected application. During JIT compilation, the JavaScript engine generates machine code from interpreted JavaScript, and when memory allocation fails under specific conditions, the engine's handling of these failure states becomes critical. The timing aspect of this vulnerability means that attackers must carefully orchestrate memory pressure to coincide with JIT compilation phases, making it a sophisticated attack vector that requires deep understanding of the browser's internal memory management and compilation processes. This type of vulnerability falls under the ATT&CK technique T1059.007 for JavaScript and T1059.006 for Visual Basic, as it exploits the JavaScript engine's execution environment to achieve code execution.
The memory corruption aspect of this vulnerability demonstrates how improper error handling during resource exhaustion can create exploitable conditions. When the JIT compiler encounters an OOM situation, the memory management routines may not properly handle cleanup operations, leading to corrupted memory structures that could be manipulated by attackers. This vulnerability represents a classic example of how complex software systems with multiple memory management layers can create unexpected interaction points where errors in one subsystem can affect others. The fact that this affects both Firefox and Thunderbird indicates a fundamental issue within the SpiderMonkey JavaScript engine that powers these applications, making the potential attack surface quite broad across Mozilla's product ecosystem. Security researchers have identified that this vulnerability requires a combination of memory exhaustion and precise timing to exploit successfully, making it more difficult to trigger than typical buffer overflow conditions but potentially more dangerous when successfully exploited.