GHSA-MJ59-H3Q9-GHFH

Vulnerability from github – Published: 2026-04-25 23:48 – Updated: 2026-05-19 15:56
VLAI
Summary
OpenClaw: MCP stdio server env could load dangerous startup variables from workspace config
Details

Affected Packages / Versions

  • Package: openclaw (npm)
  • Affected versions: < 2026.4.20
  • Patched version: 2026.4.20

Impact

Workspace MCP stdio configuration could pass dangerous process-startup environment variables such as NODE_OPTIONS, LD_PRELOAD, or BASH_ENV to the spawned MCP server process. In a malicious workspace, this could make the MCP child load attacker-controlled code when the operator starts a session that uses that MCP server.

The impact is limited to local/workspace trust boundaries and requires the operator to run OpenClaw in a workspace containing the malicious MCP configuration. Severity is therefore medium, not high/critical.

Fix

OpenClaw now filters MCP stdio environment entries through the host environment safety denylist before spawning stdio MCP servers.

Fix commits:

  • 62fa5071896e95edc7f67d1cebc70a2859e283af
  • 85d86ebc4bf3d2226d39d132a484f4f7a299fa1b

Release

Fixed in OpenClaw 2026.4.20.

Severity
5.4 (Medium)
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "openclaw"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2026.4.20"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44995"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-427",
      "CWE-454",
      "CWE-829"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-25T23:48:03Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Affected Packages / Versions\n\n- Package: `openclaw` (npm)\n- Affected versions: `\u003c 2026.4.20`\n- Patched version: `2026.4.20`\n\n## Impact\n\nWorkspace MCP stdio configuration could pass dangerous process-startup environment variables such as `NODE_OPTIONS`, `LD_PRELOAD`, or `BASH_ENV` to the spawned MCP server process. In a malicious workspace, this could make the MCP child load attacker-controlled code when the operator starts a session that uses that MCP server.\n\nThe impact is limited to local/workspace trust boundaries and requires the operator to run OpenClaw in a workspace containing the malicious MCP configuration. Severity is therefore medium, not high/critical.\n\n## Fix\n\nOpenClaw now filters MCP stdio environment entries through the host environment safety denylist before spawning stdio MCP servers.\n\nFix commits:\n\n- `62fa5071896e95edc7f67d1cebc70a2859e283af`\n- `85d86ebc4bf3d2226d39d132a484f4f7a299fa1b`\n\n## Release\n\nFixed in OpenClaw `2026.4.20`.",
  "id": "GHSA-mj59-h3q9-ghfh",
  "modified": "2026-05-19T15:56:20Z",
  "published": "2026-04-25T23:48:03Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-mj59-h3q9-ghfh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44995"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/commit/62fa5071896e95edc7f67d1cebc70a2859e283af"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/commit/85d86ebc4bf3d2226d39d132a484f4f7a299fa1b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/openclaw/openclaw"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/openclaw-arbitrary-code-execution-via-mcp-stdio-environment-variables"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "OpenClaw: MCP stdio server env could load dangerous startup variables from workspace config"
}



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