CVE-2026-92053 in Firefox
Summary
by MITRE • 09/15/2026
Privilege escalation in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156 and Firefox ESR 153.3.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 09/15/2026
The identified vulnerability resides within the CanvasWebGL subsystem of Mozilla Firefox, representing a critical privilege escalation flaw that allows an attacker to execute arbitrary code with elevated system privileges. Graphics processing units and their associated rendering engines are complex components often exposed through web technologies like WebGL, which enables hardware-accelerated 3D graphics in browsers. When such systems contain memory safety errors or logic flaws, they can be exploited by maliciously crafted web pages to break out of the browser's sandboxed environment. In this specific instance, the flaw within the CanvasWebGL component permits a user context with limited permissions to gain access to resources or execute actions reserved for higher-privileged processes, effectively bypassing standard security boundaries designed to isolate untrusted content from the underlying operating system and application data.
From a technical perspective, privilege escalation vulnerabilities in graphics drivers or rendering engines frequently stem from improper handling of memory allocations, race conditions during context switching, or insufficient validation of shader programs and buffer operations. An attacker could leverage this weakness by constructing a specialized WebGL scene or command sequence that triggers the underlying flaw within the browser's graphics stack. This exploitation path allows the malicious code to manipulate internal state variables or pointers in a way that grants it control over execution flow beyond its intended scope. The impact of such a vulnerability is severe, as successful exploitation can lead to full system compromise, data exfiltration, installation of persistent malware, or lateral movement within a network if the compromised browser instance has access to sensitive corporate resources.
This type of flaw aligns with Common Weakness Enumeration categories related to improper privilege management and memory corruption, specifically reflecting issues where an application fails to correctly enforce separation between different security levels. In terms of offensive security frameworks like MITRE ATT&CK, this vulnerability facilitates techniques associated with initial execution and defense evasion, allowing threat actors to establish a foothold while potentially bypassing endpoint detection mechanisms that rely on standard user-level activity monitoring. The ability to escalate privileges transforms a relatively contained web-based attack into a high-impact system compromise, significantly increasing the risk profile for organizations deploying Firefox as their primary browser without adequate patch management protocols.
To mitigate this risk, it is imperative that all affected systems are updated immediately to Mozilla Firefox version 156 or later, including the Extended Support Release branch at version 153.3 and subsequent patches. These updates contain the necessary code corrections that address the underlying logic errors within the CanvasWebGL component, ensuring that privilege boundaries are strictly enforced during graphics rendering operations. Organizations should implement automated patch management solutions to ensure timely deployment of security fixes across all endpoints. Additionally, administrators can enforce policies that restrict WebGL usage in high-security environments or utilize content security policies to limit interactions with potentially dangerous web elements until patches are verified as fully deployed and stable within the infrastructure.