CVE-2026-9201 — IBM Langflow OSS 1.0.0 through 1.10.3 could allow an authenticated attacker to execute…¶

Key facts

CVE-2026-9201 is a High (8.8) vulnerability: IBM Langflow OSS 1.0.0 through 1.10.3 could allow an authenticated attacker to execute…. This entry ships a detection-only PoC and a Docker test lab.


CVE	CVE-2026-9201
Severity	High (8.8)
Detection / prevention	—
PoC	poc.py
Source	2026/CVE-2026-9201/

Details¶

English | 한국어

Description¶

IBM Langflow OSS 1.0.0 through 1.10.3 could allow an authenticated attacker to execute arbitrary code due to a cryptographic weakness in the custom component validation mechanism. When the optional hardening mode that restricts execution to trusted component templates is enabled, the application validates component code using a truncated SHA‑256 hash. Because the hash comparison relies on only a portion of the digest, an attacker can craft malicious component code that collides with a trusted template hash and bypasses validation. Successful exploitation allows the attacker to introduce and execute unauthorized Python code within the Langflow process, defeating the intended security control and potentially leading to full compromise of the affected instance.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2026-9201
CVSS Score	8.8

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-9201/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-2026-9201

# 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/7282646

Generated by PoC Generator on 2026-08-09T03:32:35.950375333

Frequently asked questions¶

What is CVE-2026-9201?¶

CVE-2026-9201 is a High (8.8) vulnerability: IBM Langflow OSS 1.0.0 through 1.10.3 could allow an authenticated attacker to execute…. This entry ships a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-9201?¶

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-2026-9201?¶

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.