Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-100868",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-09-27T13:09:53.387Z",
    "dateReserved": "2026-09-27T00:20:54.407Z",
    "datePublished": "2026-09-27T13:09:53.387Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-09-27T13:09:53.387Z"
      },
      "datePublic": "2026-09-22T00:00:00.000Z",
      "title": "Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge",
      "descriptions": [
        {
          "lang": "en",
          "value": "Penpot before 2.18.0 binds the MCP server plugin WebSocket bridge to all network interfaces without authentication in single-user mode. Unauthenticated attackers on adjacent networks can connect to the WebSocket port to impersonate the Penpot browser plugin, intercept task payloads, and return forged results to the MCP client."
        }
      ],
      "affected": [
        {
          "vendor": "penpot",
          "product": "penpot",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "2.18.0"
            }
          ]
        },
        {
          "vendor": "penpot",
          "product": "@penpot/mcp",
          "collectionURL": "https://www.npmjs.com",
          "packageName": "@penpot/mcp",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "semver",
              "lessThanOrEqual": "2.15.4"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Binding to an Unrestricted IP Address",
              "cweId": "CWE-1327",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/penpot/penpot/security/advisories/GHSA-ch2q-6x56-qg5r",
          "name": "GitHub Security Advisory (GHSA-ch2q-6x56-qg5r)",
          "tags": [
            "vendor-advisory"
          ]
        },
        {
          "url": "https://github.com/penpot/penpot/commit/b5274a44766d095247037be18c1d1918ac67ddeb",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://github.com/penpot/penpot/blob/1d2c37e52c733f74017d90b0fd1ae2d074a5c33d/mcp/packages/server/src/PluginBridge.ts#L52",
          "tags": [
            "technical-description"
          ]
        },
        {
          "url": "https://github.com/penpot/penpot/security/advisories/GHSA-22qr-rp27-j9wm",
          "name": "GitHub Security Advisory (GHSA-22qr-rp27-j9wm)",
          "tags": [
            "related",
            "vendor-advisory"
          ]
        },
        {
          "url": "https://github.com/penpot/penpot",
          "tags": [
            "product"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/penpot-before-2.18.0-unauthenticated-websocket-access-via-mcp-bridge",
          "name": "VulnCheck Advisory: Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS"
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
            "attackVector": "ADJACENT_NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "availabilityImpact": "LOW",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "George Chen",
          "type": "finder"
        }
      ]
    }
  }
}