Customer Order Data Exposed via Unauthenticated gtm_server_side_order_id Cookie Manipulation in GTM Server Side WordPress Plugin

{
  "id": "2932e7e90e886413ff5a5ab5da366143795272f15c196d8b76a5e0b3f316d6af",
  "url": "https://osv.dev/vulnerability/CVE-2026-55826",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Customer Order Data Exposed via Unauthenticated gtm_server_side_order_id Cookie Manipulation in GTM Server Side WordPress Plugin",
    "summary": "The GTM Server Side plugin by stape.io implements server-side tracking on WordPress websites. From version 2.0.0 to before version 2.1.48, the WooCommerce purchase event tracking mechanism allows an unauthenticated attacker to trigger the rendering of another customer's full order data — including personally identifiable information (PII) — into the page's JavaScript dataLayer. This issue has been patched in version 2.1.48.",
    "evidence": "osv:CVE-2026-55826",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-55826",
      "aliases": [
        "CVE-2026-55826",
        "GHSA-j5j2-gr8c-8rvf"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/stape-io/gtm-server-side-wordpress-plugin",
              "type": "GIT",
              "events": [
                {
                  "introduced": "1deadba2f39c73163b82593307e22c0b1306a38b"
                },
                {
                  "fixed": "702898f57772279ca63d3f800336c1803103ea41"
                },
                {
                  "fixed": "9ff46a050028c40fad5416f2fa35be574c823434"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.0.0"
                      },
                      {
                        "fixed": "2.1.48"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "702898f57772279ca63d3f800336c1803103ea41"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "9ff46a050028c40fad5416f2fa35be574c823434"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "702898f57772279ca63d3f800336c1803103ea41"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "2.1.48"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.1.46",
            "2.1.45",
            "2.1.44",
            "2.1.43",
            "2.1.42",
            "2.1.41",
            "2.1.40",
            "2.1.39",
            "2.1.38",
            "2.1.37",
            "2.1.36",
            "2.1.35",
            "2.1.34",
            "2.1.33",
            "2.1.32",
            "2.1.31",
            "2.1.30",
            "2.1.29",
            "2.1.28",
            "2.1.27",
            "2.1.26",
            "2.1.22",
            "2.1.25",
            "2.1.24",
            "2.1.23",
            "2.1.21",
            "2.1.20",
            "2.1.19",
            "2.1.18",
            "2.1.17",
            "2.1.15",
            "2.1.14",
            "2.1.13",
            "2.1.12",
            "2.1.11",
            "2.1.10",
            "2.1.9",
            "2.1.8",
            "2.1.7",
            "2.1.6",
            "2.1.5",
            "2.1.4",
            "2.1.3",
            "2.1.2",
            "2.1.1",
            "2.1.0",
            "2.0.2",
            "2.0.1",
            "2.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55826.json"
          }
        }
      ],
      "modified": "2026-10-31T02:30:49.555018975Z",
      "provider": "osv",
      "references": [
        "https://github.com/stape-io/gtm-server-side-wordpress-plugin/releases/tag/2.1.48",
        "https://github.com/stape-io/gtm-server-side-wordpress-plugin/tree/v2.1.48",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55826.json",
        "https://github.com/stape-io/gtm-server-side-wordpress-plugin/security/advisories/GHSA-j5j2-gr8c-8rvf",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-55826",
        "https://github.com/stape-io/gtm-server-side-wordpress-plugin/commit/702898f57772279ca63d3f800336c1803103ea41",
        "https://github.com/stape-io/gtm-server-side-wordpress-plugin/commit/9ff46a050028c40fad5416f2fa35be574c823434"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-200"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55826.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-55826",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 499631,
  "published_at": "2026-10-23T13:27:45.25+00:00"
}