External risk intelligence

IBM Langflow OSS Improper Authentication Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2026-19297

IBM Langflow is a visual development tool for building LLM applications, which are commonly deployed as web-based interfaces or API endpoints. Given its role as a platform for application development and deployment, it is often exposed as a network-accessible service, making it likely to be reachable from the internet in standard deployments.

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

IBM Langflow OSS, a tool for building AI applications, has a vulnerability that could allow unauthorized access to user accounts. This issue stems from how the system handles too many login attempts, potentially enabling attackers to bypass security measures. The primary concern is to determine if our organization uses this specific technology and is exposed to this risk.

  • Account access risk from excessive login attempts.
  • Understand potential for unauthorized account access.
  • Confirm use and assess exposure of this tool.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by repeatedly attempting to log in to an affected system over the network. This could allow them to bypass security measures and gain unauthorized access to user accounts.

  • Requires network access.
  • Bypass authentication.
  • Unauthorized account access.

Live Threat

Current exploitation, exposure, and threat context

IBM Langflow OSS, when improperly configured, could allow unauthorized access to user accounts. This vulnerability may arise from an attacker repeatedly attempting to authenticate, potentially bypassing security measures. If successful, an attacker could gain access to user accounts, potentially affecting system data and user information.

  • User accounts and system data at risk.
  • Improper restriction of authentication attempts.
  • Unauthorized access to accounts.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability affects IBM Langflow, a tool for building LLM applications. Given its typical deployment as a network-accessible service, the platform or application owner is likely responsible for addressing this. The first step is to identify all instances of IBM Langflow, assess their exposure and business criticality, and then plan remediation based on the identified risk.

  • Platform or application owners should manage this.
  • Verify network reachability and business criticality first.
  • Plan remediation based on risk and impact.

Supplementary metadata

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.

Frequently asked questions

What is IBM Langflow OSS?

IBM Langflow OSS is a visual development platform designed for building applications powered by Large Language Models (LLMs). It provides a user-friendly interface that lets developers assemble complex AI workflows through drag-and-drop components, which are then typically served as web-based applications or API endpoints for users.

What does CWE-307 mean for CVE-2026-19297?

CWE-307 refers to improper restriction of excessive authentication attempts. In the context of this CVE, it means the software lacks sufficient mechanisms—such as account lockouts or rate limiting—to stop someone from guessing passwords or brute-forcing their way into an account through a high volume of login requests.

How does an attacker trigger this vulnerability?

An attacker triggers this flaw by sending a continuous stream of authentication requests to the system. The vulnerability is tied to the lack of rate limiting, so simply logging in once or occasionally will not trigger it; it requires the repeated, automated submission of login attempts to bypass standard security checks.

Why does Halo Surface Signal categorize this as external?

Halo Surface Signal identifies this as external because IBM Langflow instances are commonly deployed as network-accessible services or web interfaces. Since the vulnerability is reachable over a network without requiring prior authentication, any instance exposed to the internet can be targeted by remote attackers.

Do I need to patch my IBM Langflow installation?

You should start by performing an inventory to locate all running instances of IBM Langflow OSS in your environment. Once identified, evaluate the business criticality and network exposure of each instance to prioritize your response, then monitor official IBM support channels for guidance on remediation steps.

References