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 server's filesystem.
This vulnerability is fixed in 1.10.3.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
Low
Partial disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 5
https://github.com/langflow-ai/langflow/commit/1f39a4b9d62c9dfa1b21fa7f85e23a18…
security-advisories@github.com
https://github.com/langflow-ai/langflow/commit/94859df33acd70b2a1f816e26d68f5e8…
security-advisories@github.com
https://github.com/langflow-ai/langflow/pull/13915
security-advisories@github.com
https://github.com/langflow-ai/langflow/releases/tag/v1.10.3
security-advisories@github.com
https://github.com/langflow-ai/langflow/security/advisories/GHSA-4f6c-2vvp-gw82
security-advisories@github.com