CVE-2026-84999 (GCVE-0-2026-84999)

Vulnerability from cvelistv5 – Published: 2026-10-28 02:29 – Updated: 2026-10-28 02:29
VLAI
Title
Pie Register Premium <= 3.8.4.0 - Unauthenticated Arbitrary File Upload via piereg_file_upload AJAX Handler
Summary
The Pie Register Premium plugin for WordPress is vulnerable to Unrestricted File Type Upload in all versions up to, and including, 3.8.4.0 via the piereg_file_upload function. This is due to the plugin performing file type validation via wp_check_filetype and wp_check_filetype_and_ext but never checking whether those validation calls produced errors before move_uploaded_file() is called, combined with no nonce or capability check on the AJAX handler. This makes it possible for unauthenticated attackers to upload files of dangerous types (e.g. PHP scripts) that may be executable, which makes remote code execution possible. The server returns the generated destination filename in the response, giving the attacker the exact path needed to trigger the uploaded file.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2306 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Pie Register Pie Register Premium Affected: 0 , ≤ 3.8.4.0 (semver)
guessed Create a notification for this product.
Credits
Chu Thao Mai
Show details on NVD website
To clipboard 

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        {
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          "product": "Pie Register Premium",
          "vendor": "Pie Register",
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              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
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      ],
      "credits": [
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        }
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          "lang": "en",
          "value": "The Pie Register Premium plugin for WordPress is vulnerable to Unrestricted File Type Upload in all versions up to, and including, 3.8.4.0 via the piereg_file_upload function. This is due to the plugin performing file type validation via wp_check_filetype and wp_check_filetype_and_ext but never checking whether those validation calls produced errors before move_uploaded_file() is called, combined with no nonce or capability check on the AJAX handler. This makes it possible for unauthenticated attackers to upload files of dangerous types (e.g. PHP scripts) that may be executable, which makes remote code execution possible. The server returns the generated destination filename in the response, giving the attacker the exact path needed to trigger the uploaded file."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
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            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-434",
              "description": "CWE-434 Unrestricted Upload of File with Dangerous Type",
              "lang": "en",
              "type": "CWE"
            }
          ]
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-28T02:29:57.638Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/8385dd30-28e5-4572-8504-2f3e7029bad6?source=cve"
        },
        {
          "url": "https://pieregister.com/"
        }
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      "timeline": [
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          "time": "2026-10-27T14:10:08.000Z",
          "value": "Disclosed"
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      ],
      "title": "Pie Register Premium \u003c= 3.8.4.0 - Unauthenticated Arbitrary File Upload via piereg_file_upload AJAX Handler"
    }
  },
  "cveMetadata": {
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    "cveId": "CVE-2026-84999",
    "datePublished": "2026-10-28T02:29:57.638Z",
    "dateReserved": "2026-09-02T18:22:12.105Z",
    "dateUpdated": "2026-10-28T02:29:57.638Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
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      "percentile": "0.41515"
    },
    "nvd": {
      "cve": {
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              {
                "defaultStatus": "unaffected",
                "product": "Pie Register Premium",
                "vendor": "Pie Register",
                "versions": [
                  {
                    "lessThanOrEqual": "3.8.4.0",
                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  }
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        "cveTags": [],
        "descriptions": [
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          }
        ],
        "id": "CVE-2026-84999",
        "lastModified": "2026-10-28T13:46:33.207",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
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                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
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                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
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        "published": "2026-10-28T03:17:16.157",
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          {
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          }
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        "sourceIdentifier": "security@wordfence.com",
        "vulnStatus": "Deferred",
        "weaknesses": [
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              }
            ],
            "source": "security@wordfence.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



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