CVE-2026-100802 in Firefox
Summary
by MITRE • 09/29/2026
Uninitialized memory 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 vulnerability resides within the Graphics subsystem of Mozilla Firefox, specifically affecting the implementation of the WebGPU API. Uninitialized memory errors represent a class of defects where software reads from a memory location that has not been properly initialized with valid data prior to access. In the context of browser-based graphics processing and hardware acceleration via WebGPU, such flaws can lead to unpredictable behavior because the application may interpret random or stale data as legitimate instructions or state parameters. This type of issue is commonly categorized under CWE-457, which describes the use of an uninitialized variable, a fundamental flaw in memory safety that undermines the integrity of program execution.
The operational impact of this vulnerability depends heavily on how the browser handles the malformed graphics commands and whether an attacker can control the contents of the uninitialized memory region through crafted web content. If exploited successfully, it could potentially lead to information disclosure by leaking sensitive data stored in adjacent memory locations or cause a denial of service if the invalid state triggers a crash within the GPU process. In more severe scenarios involving specific rendering pipelines, there may be implications for code execution stability, although modern browser sandboxing and mitigations like ASLR typically limit the direct exploitability to local privilege escalation unless combined with other vulnerabilities. The risk is particularly pertinent given that WebGPU provides low-level access to graphics hardware, making precise memory management critical for maintaining system security boundaries between web content and host resources.
Mitigation strategies primarily involve relying on vendor patches, as this specific issue was addressed in Firefox version 157. Users are strongly advised to update their browsers immediately to ensure the underlying memory handling routines correctly initialize all allocated buffers before they are utilized by the graphics pipeline. From a development perspective, enforcing strict initialization practices and utilizing static analysis tools can help detect such defects early in the software lifecycle. Furthermore, enabling advanced security features within the browser configuration helps isolate potential exploits from affecting critical system components. The ATT&CK framework does not have a direct entry for uninitialized memory itself but classifies related exploitation techniques under T1059 Command and Scripting Interpreter or potentially T1203 Exploitation for Client Execution if the flaw leads to arbitrary code execution, highlighting the importance of keeping client-side software up to date to prevent such vectors from being leveraged in targeted attacks.