External risk intelligence

IBM Langflow OSS Remote Code Execution via Insecure Public Endpoint

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-19286

The vulnerability resides in a public endpoint of an open-source application designed for workflow automation. As a web-based service or API endpoint intended for interaction, such components are commonly exposed to the internet by design to facilitate remote access and integration, making public-facing deployment a standard operational pattern.

Code Injection

Langflow

1.0.0 to before 1.11.2

Halo Surface Signal: 5 out of 5 — more likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical security flaw has been identified in certain IBM Langflow open-source software, impacting its public endpoint. This vulnerability could allow an unauthorized remote attacker to execute arbitrary code, posing a significant risk to the affected systems. The main concern at this stage is to confirm if your environment utilizes this specific technology and is exposed.

Unsecured endpoint allows remote code execution.
Potential for system compromise via a public interface.
Confirm relevance and exposure within your operations.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted requests to the A2A public endpoint. This endpoint, which is exposed externally and accessible without any authentication, is improperly enforcing security restrictions. Successful exploitation could allow an attacker to execute arbitrary code on the affected system.

No authentication or special privileges needed.
Triggered via A2A public endpoint requests.
Potential for arbitrary code execution.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow a remote attacker to execute arbitrary code by exploiting improper security enforcement on the A2A public endpoint in IBM Langflow OSS. When supported by the advisory, this could impact system integrity and confidentiality.

System code and data.
Remote execution via public endpoint.
Compromised system integrity.

Operational Fix

Recommended remediation, mitigation, and detection steps

The critical vulnerability in IBM Langflow OSS affects users of versions 1.0.0 through 1.11.1. Given the nature of the A2A public endpoint, ownership likely falls to teams managing application infrastructure, platform teams, or specialized application owners responsible for the Langflow deployment. The immediate first step is to determine the scope of deployment, ascertain reachability and criticality of affected instances, and identify the accountable owner to prioritize remediation efforts based on assessed risk.

Confirm asset ownership and exposure.
Verify A2A endpoint reachability and criticality.
Plan remediation based on risk assessment.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is IBM Langflow OSS?

IBM Langflow OSS is an open-source tool designed for building and managing workflow automations. It provides a visual interface and backend services that help teams orchestrate data processing and application logic, frequently serving as an API-driven component within broader software ecosystems.

What does CWE-94 mean for CVE-2026-19286?

CWE-94 refers to improper control of generation of code, commonly known as Code Injection. In the context of this CVE, it means the software fails to properly sanitize or restrict the data it receives through its public endpoint, allowing an attacker to inject and execute their own unauthorized commands on the underlying system.

How is this vulnerability triggered?

The flaw is triggered by sending a specially crafted request to the A2A public endpoint. Because this endpoint currently lacks proper authentication, it accepts these requests without verifying the sender's identity. Requests that do not interact with this specific A2A endpoint or that are directed at hardened, non-public interfaces do not trigger this code execution path.

Is my IBM Langflow installation at risk?

Your risk depends heavily on how the instance is deployed. According to Halo Surface Signal, this vulnerability resides in a public endpoint designed for remote integration, meaning installations accessible over the internet are at the highest risk. Internal-only instances still require review, but internet-facing deployments are the primary concern due to the lack of access controls.

What should I do if I use IBM Langflow?

Begin by identifying all running instances of IBM Langflow versions 1.0.0 through 1.11.1 in your environment. Once identified, verify whether those instances expose the A2A endpoint to your network or the internet. Coordinate with the teams responsible for your application infrastructure to restrict access to these endpoints until the recommended updates or security controls can be applied.

References

www.ibm.com/support/pages/node/7284733

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.