CVE-2026-8476 — IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution…¶

Key facts

CVE-2026-8476 is a Critical (9.9) vulnerability: IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution…. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-8476
Severity	Critical (9.9)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-8476/

Details¶

English | 한국어

Description¶

IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution vulnerability in the disk-based caching mechanism. The AsyncDiskCache class uses Python's unsafe pickle.loads() function to deserialize cached objects from disk without validation, integrity verification, or authentication, enabling arbitrary code execution when malicious pickle payloads are processed. Attackers who can influence cached data through file system access, malicious workflow inputs, custom components, or API manipulation can achieve complete system compromise with the privileges of the Langflow server process.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-8476
Type	RCE
CVSS Score	9.9

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-8476/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-2026-8476

# 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://www.ibm.com/support/pages/node/7278922

Generated by PoC Generator on 2026-07-18T09:23:37.106394016

Frequently asked questions¶

What is CVE-2026-8476?¶

CVE-2026-8476 is a Critical (9.9) vulnerability: IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution…. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-8476?¶

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-2026-8476?¶

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.