n8n before 2.34.1 Cross-Project Credential Access via MCP

{
  "id": "d5cd2804fa445720092931151ab2e5362039bd95ca2563c2aa332f6702a00c07",
  "url": "https://osv.dev/vulnerability/CVE-2026-77073",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "n8n before 2.34.1 Cross-Project Credential Access via MCP",
    "summary": "n8n versions before 2.34.1 contain a credential validation bypass in the MCP create_workflow_from_code tool when authentication type is set to an expression. Attackers with a valid MCP Bearer API key and knowledge of a target credential ID can persist unauthorized cross-project credential references on workflows in different projects.",
    "evidence": "osv:CVE-2026-77073",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-77073",
      "aliases": [
        "CVE-2026-77073",
        "GHSA-vfrj-582q-mvcp"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/n8n-io/n8n",
              "type": "GIT",
              "events": [
                {
                  "introduced": "b533ecd6856fef9ba7ca096d14b1f798b9933ff6"
                },
                {
                  "fixed": "e2279d07cdc8d1aeee42607a15365ccfa98f8b27"
                },
                {
                  "introduced": "a8ecda44f7627630bc8b78cf671405157ad41c4f"
                },
                {
                  "fixed": "14c9aef0552fb4776501ca1c4589451891dd0ef4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.34.0"
                      },
                      {
                        "fixed": "2.34.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "introduced": "2.0.0"
                      },
                      {
                        "fixed": "2.33.4"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.34.0",
            "n8n@2.34.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77073.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:27.292075599Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77073.json",
        "https://github.com/n8n-io/n8n/security/advisories/GHSA-vfrj-582q-mvcp",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-77073",
        "https://www.vulncheck.com/advisories/n8n-before-cross-project-credential-access-via-mcp"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-639"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77073.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-77073",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 493880,
  "published_at": "2026-08-20T11:21:08.265+00:00"
}