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CVE-2026-34777 electron CVE debrief

Electron, a framework for building cross-platform desktop applications, had a vulnerability where the origin passed to session.setPermissionRequestHandler() was incorrectly set to the top-level page's origin instead of the requesting iframe's origin. This could lead to unintended permission grants to embedded third-party content. The issue has been patched in versions 38.8.6, 39.8.1, 40.8.1, and 41.0.0. Developers using Electron, especially those who grant permissions based on the origin parameter or webContents.getURL(), should be aware of this issue and update to the patched versions.

Vendor
electron
Product
Unknown
CVSS
MEDIUM 5.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-04
Original CVE updated
2026-07-24
Advisory published
2026-04-04
Advisory updated
2026-07-24

Who should care

Developers using Electron, especially those who grant permissions based on the origin parameter or webContents.getURL(), should be aware of this issue and update to the patched versions. Security teams and operators managing Electron-based applications should also review their exposure and take necessary actions.

Technical summary

In Electron versions prior to 38.8.6, 39.8.1, 40.8.1, and 41.0.0, when an iframe requests fullscreen, pointerLock, keyboardLock, openExternal, or media permissions, the origin passed to session.setPermissionRequestHandler() was the top-level page's origin rather than the requesting iframe's origin. This could cause apps that grant permissions based on the origin parameter or webContents.getURL() to inadvertently grant permissions to embedded third-party content. The correct requesting URL remains available via details.requestingUrl. Apps that already check details.requestingUrl are not affected.

Defensive priority

Medium priority due to potential for unintended permission grants

Recommended defensive actions

  • Update Electron to version 38.8.6, 39.8.1, 40.8.1, or 41.0.0 or later
  • Review and adjust permission-granting logic to use details.requestingUrl
  • Implement additional monitoring for unusual permission requests
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
  • Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
  • Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record was published on 2026-04-04T00:16:18.907Z and last modified on 2026-07-24T22:10:00.140Z. The NVD entry is currently Analyzed. Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. This vulnerability affects Electron versions prior to 38.8.6, 39.8.1, 40.8.1, and 41.0.0. Developers should verify their applications' exposure and update to patched versions accordingly.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-34777 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-34777

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-34777 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-34777

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.