CVE-2026-117978 in Firefox
Summary
by MITRE • 10/27/2026
Incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.
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Analysis
by VulDB Data Team • 10/27/2026
The identified security issue resides within the graphics subsystem of Mozilla Firefox, specifically involving incorrect boundary conditions during rendering operations. In software engineering, boundary condition errors typically arise when a program fails to handle edge cases correctly, such as zero-length inputs, maximum value limits, or out-of-bounds memory accesses. In the context of browser graphics processing, these flaws often manifest when the engine attempts to draw graphical elements that exceed allocated buffer sizes or interact with hardware acceleration interfaces in an unexpected manner. The vulnerability suggests a failure in input validation or array indexing logic within the rendering pipeline, potentially allowing for memory corruption or unauthorized data access if triggered by maliciously crafted web content.
From a technical perspective, this type of flaw is frequently categorized under CWE-125, which describes Out-of-bounds Read vulnerabilities, or CWE-787, indicating Out-of-bounds Write conditions depending on the specific nature of the memory violation. If an attacker can craft a webpage that triggers these incorrect boundary checks within the graphics component, they may achieve arbitrary code execution with the privileges of the user running the browser. This is particularly dangerous because modern browsers utilize multi-process architectures and sandboxing to limit damage; however, vulnerabilities in core components like graphics rendering often operate at higher privilege levels or bypass certain isolation mechanisms if they involve low-level memory manipulation via JavaScript-to-native bindings such as WebAssembly or WebGL interfaces.
The operational impact of this vulnerability centers on the potential for remote code execution through a compromised website. An attacker would need to lure a victim into visiting a specially crafted webpage that exploits these boundary errors in the graphics engine. Upon successful exploitation, the malicious script could execute arbitrary commands on the user's system, leading to data theft, installation of malware, or complete compromise of the workstation. The severity is heightened by the fact that graphics processing is fundamental to web browsing; nearly every modern website utilizes HTML5 canvas elements, WebGL, or CSS animations that interact with this subsystem, thereby increasing the attack surface significantly compared to more niche browser features.
Mozilla addressed this vulnerability in Firefox version 159 as well as in the Extended Support Release channels, specifically versions 115.44 and 153.6. These updates likely included patches that enforce stricter bounds checking on graphical buffers, improved validation of input parameters passed to native graphics libraries, or enhanced sandboxing around the rendering process. To mitigate risks associated with similar vulnerabilities in other software environments, developers should implement rigorous static analysis tools focused on memory safety and boundary checks during code review phases. Additionally, adopting defensive programming practices such as using safe container classes that automatically handle bounds checking can prevent many off-by-one errors. For end-users, maintaining up-to-date browser installations is the primary defense against exploitation of these types of logic flaws in core components.
In terms of threat intelligence frameworks, this vulnerability aligns with MITRE ATT&CK techniques related to initial access and execution via web-based attacks. Specifically, it relates to tactics where attackers leverage vulnerabilities in client-side software to gain a foothold on target systems. Security teams should monitor for indicators of compromise that suggest exploitation attempts against browser graphics engines, such as unusual memory allocation patterns or spikes in GPU usage from unexpected processes. Continuous monitoring and timely patching remain critical strategies for mitigating the risk posed by boundary condition errors in widely used web browsers.