Vulnerability-Lookup

CVE-2026-70604 (GCVE-0-2026-70604)

Vulnerability from cvelistv5 – Published: 2026-08-05 15:59 – Updated: 2026-08-05 18:41

Title

Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads

Summary

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.10, 40.9.3, 41.4.0, and 42.0.0, a custom scheme registered with supportFetchAPI: true but without corsEnabled: true was not subject to CORS enforcement. A page loaded from a remote origin could therefore fetch() or XMLHttpRequest that scheme cross-origin and read the full response body, rather than the read being blocked. Apps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. This issue is fixed in versions 39.8.10, 40.9.3, 41.4.0, and 42.0.0.

Severity

7.4 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-942 - Permissive Cross-domain Policy with Untrusted Domains

Assigner

GitHub_M

References

1 reference

URL	Tags
https://github.com/electron/electron/security/adv…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
electron	electron	Affected: < 39.8.10 Affected: >= 40.0.0-alpha.1, < 40.9.3 Affected: >= 41.0.0-alpha.1, < 41.4.0 Affected: >= 42.0.0-alpha.1, < 42.0.0

Show details on NVD website

JSON

To clipboard

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GHSA-V3J7-R9GQ-3GJW

Vulnerability from github – Published: 2026-08-05 15:59 – Updated: 2026-08-05 15:59

Summary

Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads

Details

Impact

A custom scheme registered with supportFetchAPI: true but without corsEnabled: true was not subject to CORS enforcement. A page loaded from a remote origin could therefore fetch() or XMLHttpRequest that scheme cross-origin and read the full response body, rather than the read being blocked.

Apps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. Apps that set corsEnabled: true, or that do not load untrusted content, are not affected.

Workarounds

Set corsEnabled: true on schemes that must enforce CORS, and validate the request Origin in your protocol handler before returning sensitive data.

Fixed Versions

42.0.0
41.4.0
40.9.3
39.8.10

For more information

If you have any questions or comments about this advisory, email Electron at security@electronjs.org

Severity

7.4 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "42.0.0-alpha.1"
            },
            {
              "fixed": "42.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "41.0.0-alpha.1"
            },
            {
              "fixed": "41.4.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "40.0.0-alpha.1"
            },
            {
              "fixed": "40.9.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "39.8.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-70604"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-05T15:59:45Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\nA custom scheme registered with `supportFetchAPI: true` but without `corsEnabled: true` was not subject to CORS enforcement. A page loaded from a remote origin could therefore `fetch()` or `XMLHttpRequest` that scheme cross-origin and read the full response body, rather than the read being blocked.\n\nApps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. Apps that set `corsEnabled: true`, or that do not load untrusted content, are not affected.\n\n### Workarounds\nSet `corsEnabled: true` on schemes that must enforce CORS, and validate the request `Origin` in your protocol handler before returning sensitive data.\n\n### Fixed Versions\n* `42.0.0`\n* `41.4.0`\n* `40.9.3`\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)",
  "id": "GHSA-v3j7-r9gq-3gjw",
  "modified": "2026-08-05T15:59:45Z",
  "published": "2026-08-05T15:59:45Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/electron/electron/security/advisories/GHSA-v3j7-r9gq-3gjw"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/electron/electron"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Electron: Custom protocol with supportFetchAPI but not corsEnabled allows cross-origin reads"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

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