Critical · CVSS 9.9CVE-2026-105740

Langflow: Authenticated RCE via MCP Stdio transport allows any user to execute arbitrary OS commands on the serverCVE-2026-105740

Answer in brief

CVE-2026-105740 records a Critical severity (CVSS 9.9) vulnerability in Langflow: Authenticated RCE via MCP Stdio transport allows any user to execute arbitrary OS commands on the server. The current sources do not mark it as known exploited. The current feed maps langflow-ai/langflow (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 5, 2026Updated Oct 5, 2026Source checked Oct 5, 2026First seen by HOL Oct 5, 2026Material review Oct 5, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.9
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 9.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps langflow-ai/langflow (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
langflow-ai/langflowgeneric	<1.9.0	1.9.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for langflow-ai/langflow.
Review the reported fix. Update langflow-ai/langflow to 1.9.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 5, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 5, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 5, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.