Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, any authenticated Langflow user can achieve Remote Code Execution (RCE) on the server by adding an MCP server with the "Stdio" transport. The user-supplied command field is passed directly to bash -c "exec {command}" with zero validation, no allowlisting, and no sandboxing. The command executes immediately when the server list is fetched. Additionally, the env field allows arbitrary environment variable injection (e.g., LD_PRELOAD, PATH override). This vulnerability is fixed in 1.9.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| langflow-ai | langflow | < 1.9.0 | — |
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Langflow 1.8.3 and 1.9.0 - Authenticated MCP Stdio Command Execution http/cves/2026/CVE-2026-105740.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
Advisories 1
- WID-SEC-2026-3311 Langflow: Schwachstelle ermöglicht Codeausführung BSI CERT-Bund (WID) · Oct 5, 2026