CVE-2026-70608: Electron Sandboxed Iframe Can Bypass The Vulnerability

HIGH
Advisory Identifier: GHSA-9f4c-93c8-jc8g
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CVSS 7.2
CWE-693 CWE-1021
Published
Advisory Summary

CVE-2026-70608 is a HIGH (CVSS 7.2) sandboxed iframe can bypass the vulnerability (CWE-693: Protection Mechanism Failure) affecting Electron libraries in the npm ecosystem. The issue involves sandboxed iframe can bypass the allow-popups restriction via the openurl navigation path. Remediation is available by upgrading affected packages to version 42.0.1, 41.10.3, 39.8.10.

CVE-2026-70608 at a Glance

CVE Identifier CVE-2026-70608
GHSA Identifier GHSA-9f4c-93c8-jc8g
Severity HIGH
CVSS v3.1 Base Score 7.2
CWE Classification CWE-693: Protection Mechanism Failure
Affected Product Electron
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.2

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-70608

To remediate this vulnerability, upgrade all affected Electron dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

electron fixed: 42.0.1 
npm install electron@42.0.1
electron fixed: 41.10.3 
npm install electron@41.10.3
electron fixed: 39.8.10 
npm install electron@39.8.10
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls electron

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-70608, inspect your project dependencies using npm:

npm ls electron

Analyze the terminal output to locate any version of Electron in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 42.0.1), your application is affected.

Note: The npm ls electron command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-693: Protection Mechanism Failure, where the product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. In Electron, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### 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)

CVE-2026-70608 Affected Electron Versions

3 component(s)
Fixed Versions:
42.0.141.10.339.8.10
Product / Package Ecosystem Affected Versions Fixed Version
electron
npm/electron
npm
≥ 42.0.0-alpha.1
< 42.0.1
42.0.1
electron
npm/electron
npm
≥ 40.0.0-alpha.1
< 41.10.3
41.10.3
electron
npm/electron
npm
< 39.8.10
39.8.10

References

GitHub Advisory / Wiki ADVISORY
https://github.com/electron/electron/security/advisories/GHSA-9f4c-93c8-jc8g
Electron Source Repository REPOSITORY
https://github.com/electron/electron/pull/51437
Electron Source Repository REPOSITORY
https://github.com/electron/electron/pull/51438
Electron Source Repository REPOSITORY
https://github.com/electron/electron/pull/51439
Security Fix Commit FIX COMMIT
https://github.com/electron/electron/commit/3ff23c52ab364a0afc6ab5bd7851291d3159de57
Security Fix Commit FIX COMMIT
https://github.com/electron/electron/commit/57cbe329c4ae8aab5ac5ebdcb588adc9a11de0d3
Security Fix Commit FIX COMMIT
https://github.com/electron/electron/commit/68cf8b7d9122260f6b534a69a82c701a56cf159f
Electron Source Repository REPOSITORY
https://github.com/electron/electron
Electron Release RELEASE
https://github.com/electron/electron/releases/tag/v39.8.10
Electron Release RELEASE
https://github.com/electron/electron/releases/tag/v41.10.3
Electron Release RELEASE
https://github.com/electron/electron/releases/tag/v42.0.1

Frequently Asked Questions

What is CVE-2026-70608?
CVE-2026-70608 is a security vulnerability in Electron involving Sandboxed iframe can bypass the allow-popups restriction via the OpenURL navigation path under CWE-693: Protection Mechanism Failure.
Which Electron versions are affected?
Affected versions include releases prior to 42.0.1, 41.10.3, 39.8.10 across affected packages: electron.
What version fixes CVE-2026-70608?
Upgrading to 42.0.1, 41.10.3, 39.8.10 (or the latest patched release for your respective branch) resolves the vulnerability.
Is electron affected?
Yes, electron is affected in releases prior to 42.0.1, 41.10.3, 39.8.10. Upgrade your dependency to 42.0.1, 41.10.3, 39.8.10 or later.
What is the CVSS score of CVE-2026-70608?
CVE-2026-70608 has a CVSS v3.1 base score of 7.2 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2026-70608?
CVE-2026-70608 is classified under CWE-693: Protection Mechanism Failure (The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.).
How can I check npm dependencies for CVE-2026-70608?
Run the dependency tree command: 'npm ls electron'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9f4c-93c8-jc8g",
  "modified" : "2026-08-05T17:27:18Z",
  "published" : "2026-08-05T17:27:18Z",
  "aliases" : [ "CVE-2026-70608" ],
  "summary" : "Electron: Sandboxed iframe can bypass the allow-popups restriction via the OpenURL navigation path",
  "details" : "### Impact\nA 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.\n\nApps 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.\n\n### Workarounds\nReturn `{ action: 'deny' }` from `setWindowOpenHandler` for any content you do not trust, rather than relying on the iframe sandbox alone.\n\n### Fixed Versions\n* `42.0.1`\n* `41.10.3`\n* `39.8.10`\n\n### For more information\nIf you have any questions or comments about this advisory, email Electron at [security@electronjs.org](mailto:security@electronjs.org)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "electron"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "42.0.0-alpha.1"
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      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
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    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "40.0.0-alpha.1"
      }, {
        "fixed" : "41.10.3"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "electron"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "39.8.10"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/security/advisories/GHSA-9f4c-93c8-jc8g"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/pull/51437"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/pull/51438"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/pull/51439"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/commit/3ff23c52ab364a0afc6ab5bd7851291d3159de57"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/commit/57cbe329c4ae8aab5ac5ebdcb588adc9a11de0d3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/commit/68cf8b7d9122260f6b534a69a82c701a56cf159f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/electron/electron"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/releases/tag/v39.8.10"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/releases/tag/v41.10.3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/electron/electron/releases/tag/v42.0.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1021", "CWE-693" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-05T17:27:18Z",
    "nvd_published_at" : null
  }
}