CVE-2026-34778: Electron: Service worker can spoof executeJavaScript IPC replies

April 3, 2026 (updated April 6, 2026)

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.

References

github.com/advisories/GHSA-xj5x-m3f3-5x3h
github.com/electron/electron
github.com/electron/electron/security/advisories/GHSA-xj5x-m3f3-5x3h
nvd.nist.gov/vuln/detail/CVE-2026-34778

Code Behaviors & Features

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