Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. From 42.3.1 until 42.3.3, Buffer performs incorrect byte length calculations resulting in heap buffer under/overflow. Most apps will crash and some may perform incorrect buffer allocations in the Node.js Buffer API resulting in unexpected truncation or allocation. This vulnerability is fixed in 42.3.3.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5, when a renderer calls window.open() with a target name, Electron did not correctly scope the named-window lookup to the opener's browsing context group. A renderer could navigate an existing child window that was opened by a different, unrelated renderer if both used the same target name. If that existing child was created with more permissive webPreferences (via setWindowOpenHandler's overrideBrowserWindowOptions), content loaded by the second renderer inherits those permissions. Apps are only affected if they open multiple top-level windows with differing trust levels and use setWindowOpenHandler to grant child windows elevated webPreferences such as a privileged preload script. Apps that do not elevate child window privileges, or that use a single top-level window, are not affected. Apps that additionally grant nodeIntegration: true or sandbox: false to child windows (contrary to the security recommendations) may be exposed to arbitrary code execution. This vulnerability is fixed in 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5, apps that call clipboard.readImage() may be vulnerable to a denial of service. If the system clipboard contains image data that fails to decode, the resulting null bitmap is passed unchecked to image construction, triggering a controlled abort and crashing the process. Apps are only affected if they call clipboard.readImage(). Apps that do not read images from the clipboard are not affected. This issue does not allow memory corruption or code execution. This vulnerability is fixed in 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, when an iframe requests fullscreen, pointerLock, keyboardLock, openExternal, or media permissions, the origin passed to session.setPermissionRequestHandler() was the top-level page's origin rather than the requesting iframe's origin. Apps that grant permissions based on the origin parameter or webContents.getURL() may inadvertently grant permissions to embedded third-party content. The correct requesting URL remains available via details.requestingUrl. Apps that already check details.requestingUrl are not affected. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, a service worker running in a session could spoof reply messages on the internal IPC channel used by webContents.executeJavaScript() and related methods, causing the main-process promise to resolve with attacker-controlled data. Apps are only affected if they have service workers registered and use the result of webContents.executeJavaScript() (or webFrameMain.executeJavaScript()) in security-sensitive decisions. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.0, and 41.0.0-beta.8, on macOS, app.moveToApplicationsFolder() used an AppleScript fallback path that did not properly handle certain characters in the application bundle path. Under specific conditions, a crafted launch path could lead to arbitrary AppleScript execution when the user accepted the move-to-Applications prompt. Apps are only affected if they call app.moveToApplicationsFolder(). Apps that do not use this API are not affected. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.0, and 41.0.0-beta.8.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 39.8.1, 40.7.0, and 41.0.0, apps that use offscreen rendering and allow child windows via window.open() may be vulnerable to a use-after-free. If the parent offscreen WebContents is destroyed while a child window remains open, subsequent paint frames on the child dereference freed memory, which may lead to a crash or memory corruption. Apps are only affected if they use offscreen rendering (webPreferences.offscreen: true) and their setWindowOpenHandler permits child windows. Apps that do not use offscreen rendering, or that deny child windows, are not affected. This issue has been patched in versions 39.8.1, 40.7.0, and 41.0.0.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, on Windows, app.setAsDefaultProtocolClient(protocol) did not validate the protocol name before writing to the registry. Apps that pass untrusted input as the protocol name may allow an attacker to write to arbitrary subkeys under HKCU\Software\Classes\, potentially hijacking existing protocol handlers. Apps are only affected if they call app.setAsDefaultProtocolClient() with a protocol name derived from external or untrusted input. Apps that use a hardcoded protocol name are not affected. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. From 33.0.0-alpha.1 to before 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5, apps that use offscreen rendering with GPU shared textures may be vulnerable to a use-after-free. Under certain conditions, the release() callback provided on a paint event texture can outlive its backing native state, and invoking it after that point dereferences freed memory in the main process, which may lead to a crash or memory corruption. Apps are only affected if they use offscreen rendering with webPreferences.offscreen: { useSharedTexture: true }. Apps that do not enable shared-texture offscreen rendering are not affected. To mitigate this issue, ensure texture.release() is called promptly after the texture has been consumed, before the texture object becomes unreachable. This vulnerability is fixed in 39.8.5, 40.8.5, 41.1.0, and 42.0.0-alpha.5.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0, on macOS and Linux, apps that call app.requestSingleInstanceLock() were vulnerable to an out-of-bounds heap read when parsing a crafted second-instance message. Leaked memory could be delivered to the app's second-instance event handler. This issue is limited to processes running as the same user as the Electron app. Apps that do not call app.requestSingleInstanceLock() are not affected. Windows is not affected by this issue. This issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0.