Electron: Windows opened from a sandboxed top-level document do not inherit its sandbox restrictions

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5, windows opened from a sandboxed top-level document did not inherit that document's active HTML sandbox restrictions. Untrusted content in a sandboxed top-level document that was permitted to open popups could therefore create a window with the Electron application's full origin instead of the restricted origin intended by the sandbox. Applications that deny such popups with setWindowOpenHandler are not affected. This issue is fixed in versions 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5.

Source published

29 Sep 2026 16:51:26 UTC

Source modified

29 Sep 2026 17:20:35 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5, windows opened from a sandboxed top-level document did not inherit that document's active HTML sandbox restrictions. Untrusted content in a sandboxed top-level document that was permitted to open popups could therefore create a window with the Electron application's full origin instead of the restricted origin intended by the sandbox. Applications that deny such popups with setWindowOpenHandler are not affected. This issue is fixed in versions 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5.

Source published

Sep 29, 2026, 4:51:26 PM (timezone not stated)

Source modified

Sep 29, 2026, 5:20:35 PM (timezone not stated)

Observed here

9 Nov 2026 05:03:35 UTC

Source terms

ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5, windows opened from a sandboxed top-level document did not inherit that document's active HTML sandbox restrictions. Untrusted content in a sandboxed top-level document that was permitted to open popups could therefore create a window with the Electron application's full origin instead of the restricted origin intended by the sandbox. Applications that deny such popups with setWindowOpenHandler are not affected. This issue is fixed in versions 41.10.6, 42.9.2, 43.4.1, and 44.0.0-beta.5.

Source published

29 Sep 2026 17:17:07 UTC

Source modified

15 Oct 2026 13:58:37 UTC

Observed here

25 Oct 2026 04:17:26 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

CVSS 3.1 · [email protected] · Primary · 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

### Impact Windows opened from a sandboxed top-level document did not inherit that document's HTML `sandbox` restrictions, so content that was meant to run sandboxed could open a window with the app's full origin. GHSA-hq2x-r82h-9wj4 covers the same issue for sandboxed iframes. Apps are only affected if they render untrusted content in a sandboxed top-level document that allows popups. Apps that deny popups from untrusted content with `setWindowOpenHandler` are not affected. ### Workarounds Return `{ action: 'deny' }` from `setWindowOpenHandler` for windows opened by untrusted content. ### Fixed Versions * `44.0.0-beta.5` * `43.4.1` * `42.9.2` * `41.10.6` ### For more information If you have any questions or comments about this advisory, email us at [[email protected]](mailto:[email protected])

Source published

29 Sep 2026 18:05:11 UTC

Source modified

29 Sep 2026 18:15:04 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

Publisher rating · HIGH