HighGHSA-9f4c-93c8-jc8gCVE-2026-70608

Electron: Sandboxed iframe can bypass the allow-popups restriction via the OpenURL navigation path

Published 5 Aug 2026 · Updated 20 Aug 2026

Affected packages

electronnpm

Affected: >=42.0.0-alpha.1 <42.0.1
Fixed in: 42.0.1

Update to the fixed version for your release line, for example:npm install electron@42.0.1

electronnpm

Affected: >=40.0.0-alpha.1 <41.10.3
Fixed in: 41.10.3

Update to the fixed version for your release line, for example:npm install electron@41.10.3

electronnpm

Affected: <39.8.10
Fixed in: 39.8.10

Update to the fixed version for your release line, for example:npm install electron@39.8.10

Details

Impact

A sandboxed iframe without the allow-popups keyword could still open a new window (or trigger setWindowOpenHandler) with no user interaction, because new-window navigations taking the OpenURL path did not apply the iframe sandbox popup restriction.

Apps that embed untrusted content in sandboxed iframes and rely on the absence of allow-popups to prevent window creation are affected. Apps that deny window creation in setWindowOpenHandler, or that do not embed untrusted content in sandboxed iframes, are not affected.

Workarounds

Return { action: 'deny' } from setWindowOpenHandler for any content you do not trust, rather than relying on the iframe sandbox alone.

Fixed Versions

42.0.1
41.10.3
39.8.10

For more information

If you have any questions or comments about this advisory, email Electron at [security@electronjs.org](mailto:security@electronjs.org)

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.