CVE-2026-92052 in Firefox
Summary
by MITRE • 09/15/2026
Privilege escalation due to uninitialized memory in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156 and Firefox ESR 153.3.
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Analysis
by VulDB Data Team • 09/15/2026
The identified security flaw resides within the Graphics subsystem, specifically affecting the CanvasWebGL component of Mozilla Firefox browsers. This issue is classified as a memory safety vulnerability characterized by uninitialized memory access, which serves as a critical precursor to potential privilege escalation attacks. In software engineering and cybersecurity frameworks such as CWE-457 (Use of Uninitialized Variable), this type of defect occurs when a program attempts to read from a memory location that has not been properly initialized with a defined value. Within the context of WebGL rendering, where complex graphical computations are performed frequently and often in real-time, the handling of temporary variables or buffer states is paramount for system stability and security. When these values remain uninitialized, they may contain residual data from previous operations or arbitrary memory contents, leading to unpredictable behavior during execution.
The operational impact of this vulnerability is severe due to its potential to facilitate privilege escalation. An attacker who can craft a malicious webpage containing specially designed WebGL content could exploit the uninitialized memory state to manipulate control flow within the browser process. By leveraging specific sequences of graphical commands or shader executions, it may be possible to cause an out-of-bounds read or write operation that allows the attacker to execute arbitrary code with elevated privileges beyond those granted to standard web sandboxing policies. This effectively breaks the isolation boundaries intended by modern browsers, potentially allowing access to sensitive user data, system resources, or further lateral movement within a compromised environment. Such exploits align closely with MITRE ATT&CK techniques related to privilege escalation and memory corruption exploitation, highlighting the critical nature of addressing these low-level defects in high-performance graphics libraries.
Mitigation for this vulnerability was implemented through code corrections that ensure all relevant variables are properly initialized before use during WebGL context creation and rendering operations. Users must update their browsers to Firefox version 156 or Firefox Extended Support Release (ESR) version 153.3, where these patches have been integrated into the stable release channels. It is imperative for organizations relying on ESR versions to verify that they are running a build equal to or newer than 153.3 to ensure protection against this specific threat vector. Additionally, developers integrating WebGL technologies should adhere strictly to memory initialization best practices and utilize static analysis tools capable of detecting uninitialized variable usage in C++ codebases, which form the core of browser rendering engines. Regular security audits and adherence to secure coding standards are essential to prevent similar vulnerabilities from being introduced into graphics processing components in future software updates.