CVE-2026-84731 — An unauthenticated remote attacker can bypass authentication and gain full access to…¶

Key facts

CVE-2026-84731 is a Critical (9.8) vulnerability: An unauthenticated remote attacker can bypass authentication and gain full access to…. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-84731
Severity	Critical (9.8)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-84731/

Details¶

English | 한국어

Description¶

An unauthenticated remote attacker can bypass authentication and gain full access to administrative API endpoints in Nutanix Prism Element by including a crafted internal management HTTP header. The vulnerability is caused by a misconfiguration in the application's authentication filters.

Consequently, the server responds with a Set-Cookie header containing a valid JSESSIONID. This session cookie decodes to a JSON Web Token (JWT) granting maximum cluster administrative privileges. Successful exploitation allows the attacker to execute root-level commands on all Controller VMs (CVMs) in the cluster, leading to complete cluster destruction and unauthorized access to VM memory and virtual disks.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-84731
CVSS Score	9.8

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-84731/poc.py

Usage¶

# Run PoC against target
python3 poc.py --target <TARGET_URL>

# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>

⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.

Test Lab¶

This repository includes a Docker-based test environment with both vulnerable and patched applications.

Quick Start¶

# Clone and navigate to CVE directory
cd CVE-2026-84731

# Start both applications
docker-compose up -d

# Run tests
./run-tests.sh    # Linux/Mac
./run-tests.ps1   # Windows PowerShell

Application Endpoints¶

Application	URL	Status
Vulnerable App	http://localhost:8080	Shows vulnerability
Patched App	http://localhost:8081	Demonstrates fix

Directory Structure¶

├── README.md           # English documentation
├── README_KO.md        # Korean documentation
├── poc.py              # PoC detection script
├── docker-compose.yml  # Container orchestration
├── run-tests.sh        # Linux/Mac test runner
├── run-tests.ps1       # Windows test runner
├── vulnerable-app/     # Vulnerable version
│   ├── app.py
│   ├── Dockerfile
│   └── requirements.txt
└── patched-app/        # Fixed version
    ├── app.py
    ├── Dockerfile
    └── requirements.txt

References¶

https://download.nutanix.com/alerts/Security_Advisory_0058.pdf
https://portal.nutanix.com/page/documents/list?type=software&filterKey=software&filterVal=AOS
https://www.nutanix.com/support

Generated by PoC Generator on 2026-10-16T04:24:45.044188297

Frequently asked questions¶

What is CVE-2026-84731?¶

CVE-2026-84731 is a Critical (9.8) vulnerability: An unauthenticated remote attacker can bypass authentication and gain full access to…. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-84731?¶

Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.

How do I block or mitigate CVE-2026-84731?¶

Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.

For authorized security testing and research only. See the full source and NVD record.