CVE-2025-14322 in Firefox
Summary
by MITRE • 12/09/2025
Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability affects Firefox < 146, Firefox ESR < 115.31, Firefox ESR < 140.6, Thunderbird < 146, and Thunderbird < 140.6.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 01/06/2026
This vulnerability represents a critical sandbox escape flaw within the Graphics: CanvasWebGL component of Mozilla Firefox and Thunderbird applications. The issue stems from improper boundary condition handling that allows malicious actors to bypass security restrictions designed to isolate web content from the underlying operating system. Such sandbox escape vulnerabilities are particularly dangerous as they undermine fundamental security mechanisms that protect users from malicious code execution. The vulnerability affects multiple product versions including Firefox browsers prior to 146, Firefox ESR versions before 115.31 and 140.6, and corresponding Thunderbird versions, indicating a widespread impact across both browser and email client platforms. The flaw specifically targets the WebGL graphics rendering subsystem which is commonly used for web-based 3D graphics and visual processing.
The technical implementation of this vulnerability involves memory corruption issues that arise when the WebGL component processes certain graphical operations without proper validation of input parameters. When boundary conditions are not correctly enforced during graphics processing, attackers can manipulate memory layouts to execute arbitrary code outside of the intended sandboxed environment. This type of vulnerability typically manifests through buffer overflow conditions or memory access violations that occur when the graphics subsystem handles malformed or unexpected input data. The flaw demonstrates weaknesses in input validation and memory management practices within the graphics rendering pipeline, creating opportunities for privilege escalation and system compromise. According to CWE classification, this vulnerability aligns with CWE-129 which covers insufficient validation of length of inputs, and CWE-125 which addresses out-of-bounds read conditions. The attack surface is particularly concerning given that WebGL is widely used in modern web applications and browser-based games, making exploitation relatively accessible to threat actors.
The operational impact of this vulnerability extends beyond simple code execution to potentially enable full system compromise and persistent access to affected systems. Once an attacker successfully escapes the sandbox, they can access system resources, read sensitive files, modify system settings, and potentially install additional malware. The vulnerability affects both desktop and mobile platforms where these applications are deployed, creating widespread exposure across different computing environments. Organizations running affected versions of Firefox or Thunderbird face significant risk of data breaches, system infiltration, and potential lateral movement within their networks. The attack vector typically involves visiting malicious websites or opening compromised email attachments that contain crafted WebGL content designed to trigger the boundary condition flaw. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1566 for credential harvesting, as successful exploitation can lead to further reconnaissance and privilege escalation activities. The widespread adoption of WebGL in web applications makes this vulnerability particularly attractive to threat actors seeking scalable attack vectors.
Mitigation strategies should prioritize immediate patching of all affected software versions to address the underlying boundary condition flaws. Organizations should implement network-based protections such as web application firewalls and content filtering to block known malicious WebGL content. Browser hardening measures including disabling WebGL when not required, implementing strict content security policies, and using sandboxing configurations should be considered as additional protective layers. Security monitoring should focus on detecting unusual graphics processing patterns or memory access violations that might indicate exploitation attempts. Regular security assessments of web applications and browser configurations are essential to identify potential exposure points. System administrators should also consider implementing privileged access controls and network segmentation to limit the potential impact of successful exploitation. The vulnerability highlights the importance of maintaining up-to-date software configurations and implementing robust security monitoring to detect and respond to emerging threats in graphics rendering components. Organizations should also review their incident response procedures to ensure readiness for potential sandbox escape incidents that could compromise system integrity and user data confidentiality.