CVE-2026-102673

Electron drops inherited HTML sandbox restrictions for popups opened through OpenURLFromTab

Workarounds

Use setWindowOpenHandler on the parent WebContents to deny or constrain popups opened from sandboxed frames, or do not apply allow-popups to sandboxed iframes that render untrusted content.

Fixed Versions

• 43.0.0
• 42.5.2
• 41.10.4

For more information

If you have any questions or comments about this advisory, email us at [email protected]

Popups opened from a sandboxed iframe through a link (for example target="_blank" or a middle-click) did not inherit the iframe's HTML sandbox restrictions. Content that was meant to run sandboxed could open a popup with the embedding app's full origin, gaining access to that origin's cookies, storage, and same-origin scripting.

Apps are only affected if they embed untrusted content in iframes sandboxed with allow-scripts allow-popups. Apps that do not embed untrusted content in sandboxed iframes are not affected.

CVE-2026-102673 has a CVSS score of 8.2 (High). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (41.10.4, 42.5.2, 43.0.0); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

1. What is CVE-2026-102673? CVE-2026-102673 is a high-severity security vulnerability in electron (npm), affecting versions < 41.10.4. It is fixed in 41.10.4, 42.5.2, 43.0.0.
2. How severe is CVE-2026-102673? CVE-2026-102673 has a CVSS score of 8.2 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of electron are affected by CVE-2026-102673? electron (npm) versions < 41.10.4 is affected.
4. Is there a fix for CVE-2026-102673? Yes. CVE-2026-102673 is fixed in 41.10.4, 42.5.2, 43.0.0. Upgrade to this version or later.
5. Is CVE-2026-102673 exploitable, and should I be worried? Whether CVE-2026-102673 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-102673 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-102673?
   • Upgrade electron to 41.10.4 or later
   • Upgrade electron to 42.5.2 or later
   • Upgrade electron to 43.0.0 or later

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