GHSA-3C8V-CFP5-9885

Vulnerability from github – Published: 2026-04-03 02:43 – Updated: 2026-04-06 23:11
VLAI?
Summary
Electron: Out-of-bounds read in second-instance IPC on macOS and Linux
Details

Impact

On macOS and Linux, apps that call app.requestSingleInstanceLock() were vulnerable to an out-of-bounds heap read when parsing a crafted second-instance message. Leaked memory could be delivered to the app's second-instance event handler.

This issue is limited to processes running as the same user as the Electron app.

Apps that do not call app.requestSingleInstanceLock() are not affected. Windows is not affected by this issue.

Workarounds

There are no app side workarounds, developers must update to a patched version of Electron.

Fixed Versions

  • 41.0.0
  • 40.8.1
  • 39.8.1
  • 38.8.6

For more information

If there are any questions or comments about this advisory, please email security@electronjs.org

Severity ?
5.3 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:L
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "38.8.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "39.0.0-alpha.1"
            },
            {
              "fixed": "39.8.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "40.0.0-alpha.1"
            },
            {
              "fixed": "40.8.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "electron"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "41.0.0-alpha.1"
            },
            {
              "fixed": "41.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34776"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-03T02:43:59Z",
    "nvd_published_at": "2026-04-04T00:16:18Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nOn macOS and Linux, apps that call `app.requestSingleInstanceLock()` were vulnerable to an out-of-bounds heap read when parsing a crafted second-instance message. Leaked memory could be delivered to the app\u0027s `second-instance` event handler.\n\nThis issue is limited to processes running as the same user as the Electron app.\n\nApps that do not call `app.requestSingleInstanceLock()` are not affected. Windows is not affected by this issue.\n\n### Workarounds\nThere are no app side workarounds, developers must update to a patched version of Electron.\n\n### Fixed Versions\n* `41.0.0`\n* `40.8.1`\n* `39.8.1`\n* `38.8.6`\n\n### For more information\nIf there are any questions or comments about this advisory, please email [security@electronjs.org](mailto:security@electronjs.org)",
  "id": "GHSA-3c8v-cfp5-9885",
  "modified": "2026-04-06T23:11:04Z",
  "published": "2026-04-03T02:43:59Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/electron/electron/security/advisories/GHSA-3c8v-cfp5-9885"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34776"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/electron/electron"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Electron: Out-of-bounds read in second-instance IPC on macOS and Linux"
}


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