Langflow is a tool for building and deploying AI-powered agents and workflows. From 1.5.0 until 1.10.3, an IP spoofing vulnerability in the Model Context Protocol (MCP) configuration installation endpoint (POST /api/v1/mcp/project/{project_id}/install) allowed authenticated remote attackers to bypass the local-only access restriction. By sending a spoofed X-Forwarded-For: 127.0.0.1 header, an attacker could make the server treat the request as originating from localhost, letting them write/overwrite an MCP client configuration file on the servers filesystem. This vulnerability is fixed in 1.10.3.
Weakness
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/21.html
- https://cwe.mitre.org/data/definitions/22.html
- https://cwe.mitre.org/data/definitions/459.html
- https://cwe.mitre.org/data/definitions/461.html
- https://cwe.mitre.org/data/definitions/473.html
- https://cwe.mitre.org/data/definitions/476.html
- https://cwe.mitre.org/data/definitions/59.html
- https://cwe.mitre.org/data/definitions/60.html
- https://cwe.mitre.org/data/definitions/667.html
- https://cwe.mitre.org/data/definitions/94.html
References
- https://github.com/langflow-ai/langflow/commit/1f39a4b9d62c9dfa1b21fa7f85e23a180c351b72
- https://github.com/langflow-ai/langflow/commit/94859df33acd70b2a1f816e26d68f5e89a7e5639
- https://github.com/langflow-ai/langflow/pull/13915
- https://github.com/langflow-ai/langflow/releases/tag/v1.10.3
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-4f6c-2vvp-gw82
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-4f6c-2vvp-gw82