CVE-2026-70601: Electron: Context isolation bypass via Function.prototype.bind hijack

Apps that expose Promise-returning functions to web content via contextBridge may be vulnerable to a context isolation bypass. Untrusted web content could obtain access to the isolated preload world and, through it, every capability the preload script has. In renderers without a sandbox, or with nodeIntegration enabled, this may escalate to Node.js access.

Apps are affected if they expose Promise-returning functions via contextBridge — the standard pattern for wrapping ipcRenderer.invoke — in windows that load untrusted content. Apps that never load untrusted content in those windows are not affected.