Hacking, PenTest, and Cybersecurity Tools for Your Security Arsenal!
CVE-2025-3248 — Educational analysis and proof-of-concept exploit for CVE-2025-3248, a critical unauthenticated code injection vulnerability in Langflow, including mitigation guidance. | Kitploit
Educational analysis and proof-of-concept exploit for CVE-2025-3248, a critical unauthenticated code injection vulnerability in Langflow, including mitigation guidance.
Langflow is an open-source visual framework for building multi-agent and RAG applications. To allow developers to write custom Python components, it provides logic to validate and execute code snippets on the fly.
The Root Cause
Lack of Input Sanitization: In versions prior to 1.3.0, the endpoint accepts Python code strings from user requests.
/api/v1/validate/code
Insecure Execution: The backend processes this code directly using dynamic evaluation mechanisms (such as exec() or similar runtime evaluators) without sufficient sandboxing, input sanitization, or execution restriction.
No Authentication Required: The endpoint is exposed by default to unauthenticated users, allowing anyone with network access to trigger execution.
Consequently, an attacker can supply Python system-execution payloads (such as utilizing the os or subprocess modules) to execute arbitrary commands under the system privileges of the Langflow service runner.
🛠️ Mitigation & Hardening
If you are running or administering Langflow instances, apply the following controls:
1. Upgrade Immediately
The vulnerability is resolved in Langflow version 1.3.0 and later. Ensure your deployment pipelines are updated:
root@kitploit:~
pip install --upgrade langflow
2. Network Segmentation & Access Control
Restrict API Exposure: Never expose Langflow's admin interface or API endpoints directly to the public internet. Use a Reverse Proxy (e.g., Nginx, Traefik) or a Cloud API Gateway to restrict access.
Enable Authentication: Ensure robust user authentication is enforced on all API routes before they reach the backend service.
3. Container Isolation (Principle of Least Privilege)
If running Langflow within Docker or Kubernetes:
Do not run the container process as root.
Use container security profiles (AppArmor, Seccomp) to restrict system calls.
Use a read-only root filesystem where possible and restrict network egress from the container to only trusted destinations.
⚠️ Disclaimer
This documentation is maintained solely for authorized security assessment, defense hardening, and educational purposes. Ensure all testing is restricted to self-hosted, authorized laboratory environments.
zoly-zoly/cve-2025-3248
