CVE-2026-100764 in Firefox
Summary
by MITRE • 09/29/2026
Privilege escalation due to incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 157.
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Analysis
by VulDB Data Team • 09/29/2026
The identified security flaw resides within the WebGPU implementation of Mozilla Firefox, specifically affecting the graphics processing subsystem responsible for handling shader execution and memory management boundaries. As a high-performance graphics API designed to provide efficient access to GPU capabilities on the web, WebGPU relies heavily on strict adherence to boundary conditions when allocating resources and validating input data from untrusted sources such as remote websites or malicious scripts. The vulnerability stems from an incorrect evaluation of these boundaries during runtime operations, which allows for a failure in proper isolation between different execution contexts or memory segments within the browser's sandboxed environment. This type of architectural weakness is characteristic of CWE-190 Integer Overflow or Wraparound and CWE-787 Out-of-bounds Write vulnerabilities, where the software fails to properly validate input data before using it as an index or size parameter for memory operations.
From a technical perspective, this boundary condition error likely permits an attacker who can execute arbitrary JavaScript within a WebGPU context to manipulate internal state variables in ways that bypass expected constraints. By crafting specific shader programs or API calls that trigger the flawed logic, an adversary may achieve out-of-bounds read access, leading to information disclosure of sensitive memory contents such as credentials stored in other tabs or process data. More critically, if the boundary check failure results in a write operation outside allocated buffers, it could lead to arbitrary code execution within the browser's content process sandbox. This represents a significant escalation from standard cross-site scripting risks to potential full system compromise depending on how effectively the operating system and browser sandboxing mechanisms contain the breach. The ATT&CK framework categorizes such exploitation techniques under T1059 Command and Scripting Interpreter for initial access via web browsers, followed by T1068 Exploitation for Privilege Escalation if the sandbox is successfully breached to gain higher-level privileges on the host system.
The operational impact of this vulnerability extends beyond individual user compromise to broader organizational security postures that rely on Firefox as their primary enterprise browser. Attackers can leverage this flaw in phishing campaigns or drive-by download scenarios where a victim visits a malicious webpage utilizing WebGPU features. Since WebGPU is increasingly adopted for complex web applications including 3D rendering, machine learning inference in the browser, and advanced data visualization, the attack surface remains relevant across many modern web platforms. Successful exploitation could allow attackers to exfiltrate sensitive corporate data, install persistent malware, or use the compromised device as a pivot point within an internal network. The severity is further amplified by the fact that WebGPU operates at a low level with significant hardware access, making traditional memory corruption defenses less effective if boundary checks are not rigorously enforced in the underlying C++ codebase of the browser engine.
Mitigation strategies primarily involve applying the vendor-provided patch released in Firefox version 157, which corrects the logical errors in boundary validation routines within the WebGPU component. Organizations should enforce automated update policies to ensure all client machines receive this security fix promptly. In environments where immediate patching is not feasible due to compatibility concerns with legacy applications relying on specific browser behaviors, network-level controls such as web content filtering can be employed to block access to domains known for hosting exploit kits or suspicious WebGPU-heavy scripts. Additionally, enabling strict Content Security Policies and sandboxing configurations in Firefox helps limit the potential blast radius of any successful exploitation attempt by restricting API permissions and isolating processes more rigorously. Continuous monitoring for anomalous GPU usage patterns or unexpected memory allocations can also serve as an early detection mechanism for attempts to exploit this class of vulnerabilities before they result in full compromise.