External risk intelligence

Firefox Graphics WebGPU Component Incorrect Boundary Conditions Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2026-16393

This vulnerability exists within a web browser's graphics component. While browsers interact with the internet, this specific issue requires a user to navigate to a malicious site or interact with untrusted content within the client-side application environment. It is not a network-accessible service, gateway, or externally reachable appliance.

Memory Corruption

Mozilla Firefox

before 153.0.0before 153.0

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory concerns a critical vulnerability identified in the Graphics: WebGPU component of Firefox, which has been addressed in version 153. The issue relates to improper handling of data boundaries, potentially allowing for significant impacts on confidentiality and availability. While the vulnerability exists within a browser's graphics component and requires user interaction with malicious content, its critical rating warrants attention to understand its potential relevance and exposure within the organization.

Graphics flaw affects browser components.
Critical rating suggests potential high impact.
Confirm relevance and exposure to affected systems.

Attack Path

How an attacker could exploit the issue

A distant attacker could target this vulnerability by directing a user to a specially crafted web page or content that abuses flawed boundary checks within the Graphics: WebGPU component. When the browser processes this malicious content, it can lead to severe security consequences.

Requires user interaction with malicious content.
Triggered by processing crafted graphics data.
Can lead to significant information disclosure and denial of service.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability in the Graphics: WebGPU component could allow an attacker to potentially impact the integrity and availability of a user's system when interacting with malicious web content. The issue arises from incorrect boundary conditions, which, when exploited, could lead to denial of service or unauthorized modification of data.

System integrity and availability.
Through malicious web content.
System instability or data corruption.

Operational Fix

Recommended remediation, mitigation, and detection steps

To address this vulnerability in the Graphics: WebGPU component, platform and security teams should collaborate. The first practical step is to identify all systems running the affected browser, confirm exposure to the internet or untrusted user interaction, and determine which systems are business-critical. Once these are identified, the accountable owner should be found to plan remediation based on the assessed risk.

Platform and Security teams own resolution.
Verify browser reachability and criticality.
Plan remediation based on exposure.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the Firefox WebGPU component?

WebGPU is a modern graphics API integrated into the Firefox browser. It allows web applications to perform high-performance 3D graphics and data-parallel computations by accessing the computer's underlying graphics processing unit (GPU). By offloading these complex tasks from the CPU, it enables sophisticated visual experiences and accelerated processing directly within your browser window.

What does CVE-2026-16393 mean by incorrect boundary conditions?

This vulnerability, classified as CWE-119, occurs when the software fails to properly check the limits of memory buffers. In the context of the WebGPU component, the browser may read or write data outside the designated space intended for graphics processing. This memory safety flaw can lead to unauthorized access to information or cause the application to crash, resulting in a denial of service.

How is this WebGPU vulnerability triggered?

An attacker triggers this bug by enticing a user to visit a specially crafted website or interact with malicious online content. The vulnerability relies on the browser's graphics engine attempting to process this hostile data. It is important to note that merely having the browser installed does not trigger the flaw; the browser must actively parse the malicious graphics data for the memory boundary violation to occur.

Is my system at risk according to Halo Surface Signal?

Halo Surface Signal indicates that while this is a critical issue, it is not a traditional network-accessible service. Because the vulnerability exists within the client-side browser environment, it requires user interaction with untrusted content to manifest. Systems are most relevant when they are actively used to browse the internet, as the risk is tied to the websites a user visits rather than direct remote attacks against a background server or appliance.

What are the first steps to address this Firefox flaw?

The most effective response is to update Firefox to version 153 or later, as this patch corrects the underlying boundary logic. Before applying the update, organizations should inventory which systems run the browser and prioritize those with high exposure to untrusted web content. Coordinating with your platform and security teams ensures that these systems are updated systematically to mitigate the risk of data disclosure or service disruption.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.