Langflow

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

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of 28 Oct 2026. If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?

EPSS score, percentile 64.2 of all scored records. A probability estimated by FIRST, not a report of exploitation.

CISA's SSVC assessment in the CVE record lists exploitation as poc.

How severe?

9.9 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

< 1.9.0

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 29 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-29_0000Z, as of 29 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Affected products and versions

As listed in the CVE record.

langflow-ai langflow
Status	Versions
Affected	< 1.9.0

Source: CVE List V5 (CVE Program), cve_2026-10-29_0000Z, as of 29 Oct 2026. About the data.

About this vulnerability

Summary: CVE record, as of 29 Oct 2026.

CISA has not added CVE-2026-105740 to its Known Exploited Vulnerabilities (KEV) catalog, as of 28 Oct 2026.
The CVE record was published on 5 Oct 2026.
The CVE record carries a CVSS v3.1 base score of 9.9 (Critical), given by its CNA.
FIRST's EPSS model puts the probability of exploitation in the next 30 days at 1% (percentile 64.2), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
CISA's SSVC assessment in the CVE record: exploitation poc, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-29_0000Z, as of 29 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 29 Oct 2026. About the data.

Description

Langflow: Authenticated RCE via MCP Stdio transport allows any user to execute arbitrary OS commands on the server

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.

Source: CVE List V5 (CVE Program), cve_2026-10-29_0000Z, as of 29 Oct 2026. About the data.

Weakness

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.

Timeline

Date	Event
5 Oct 2026	CVE record published
6 Oct 2026	CVE record last updated

References

Known exploited Langflow vulnerabilities

CVE-2026-0770: Langflow Inclusion of Functionality from Untrusted Control Sphere Vulnerability (added 21 Jul 2026)
CVE-2026-55255: Langflow Authorization Bypass Through User-Controlled Key Vulnerability (added 7 Jul 2026)
CVE-2025-34291: Langflow Origin Validation Error Vulnerability (added 21 May 2026)
CVE-2026-33017: Langflow Code Injection Vulnerability (added 25 Mar 2026)
CVE-2025-3248: Langflow Missing Authentication Vulnerability (added 5 May 2025)