CVE-2026-70607 in Electron
Summary
by MITRE • 08/05/2026
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3, some window options supplied by web content in the window.open() features string were applied to the new BrowserWindow without an allowlist. Untrusted content could set window options it should not control, including options that cause the main process to access attacker-chosen file or network paths, when untrusted content can call window.open() and the app does not override child window options via setWindowOpenHandler or overrideBrowserWindowOptions. This issue is fixed in 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3.
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Analysis
by VulDB Data Team • 08/05/2026
This vulnerability affects the Electron framework, which enables developers to build cross-platform desktop applications using web technologies including JavaScript, HTML, and CSS. The security flaw exists in versions prior to 39.8.8, 40.9.0, 41.2.1, and 42.0.0-beta.3 where the window.open() function processes features string parameters without proper validation. When untrusted web content executes window.open(), it can manipulate window options that should be restricted to prevent unauthorized access to system resources.
The technical implementation flaw stems from the absence of an allowlist mechanism for window options in the BrowserWindow creation process. Specifically, when web content calls window.open() with a features string containing parameters such as 'file://' or 'http://' paths, these options are directly applied to the new BrowserWindow instance without verification. This oversight allows malicious actors to exploit the functionality by injecting attacker-controlled file or network paths into the window configuration, potentially enabling unauthorized system access.
The operational impact of this vulnerability is significant as it creates a privilege escalation vector through which untrusted content can gain access to sensitive system resources. Attackers can leverage this flaw to cause the main process to access arbitrary files or network locations that would normally be restricted, effectively bypassing security boundaries between the renderer process and the main process. This vulnerability particularly affects applications that do not implement proper window handling overrides through setWindowOpenHandler or overrideBrowserWindowOptions methods.
Organizations using Electron frameworks should immediately upgrade to versions 39.8.8, 40.9.0, 41.2.1, or 42.0.0-beta.3 to remediate this vulnerability. Additionally, developers should implement proper window handling mechanisms by utilizing setWindowOpenHandler to intercept and validate window.open() calls, and overrideBrowserWindowOptions to ensure that untrusted content cannot manipulate critical window properties. This vulnerability aligns with CWE-264, which addresses permissions, privileges, and access controls, and maps to ATT&CK techniques involving privilege escalation and arbitrary code execution through web-based attack vectors. Organizations should also consider implementing Content Security Policy headers and sandboxing measures to further mitigate potential exploitation risks.