langflow-ai Langflow up to 1.8.1 Public Flow Build Endpoint eval injection

Summaryinfo

A vulnerability has been found in langflow-ai Langflow up to 1.8.1 and classified as critical. Affected is an unknown function of the component Public Flow Build Endpoint. The manipulation leads to eval injection. This vulnerability is referenced as CVE-2026-33017. Remote exploitation of the attack is possible. Furthermore, an exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in langflow-ai Langflow up to 1.8.1. This issue affects an unknown part of the component Public Flow Build Endpoint. The manipulation with an unknown input leads to a eval injection vulnerability. Using CWE to declare the problem leads to CWE-95. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes code syntax before using the input in a dynamic evaluation call (e.g. "eval"). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/build_public_tmp/{flow_id}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/code by adding authentication. The build_public_tmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-33017. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are unknown but a public exploit is available.

The exploit is available at exploit-db.com. It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 03/25/2026 with a due date of 04/08/2026:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (52627). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• langflow-ai

Name

• Langflow

Version

• 1.8.0
• 1.8.1

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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