FlowiseAI Flowise up to 3.0.12 API Endpoint createLead dynamically-determined object attributes

Summaryinfo

A vulnerability was found in FlowiseAI Flowise up to 3.0.12. It has been classified as critical. This affects the function createLead of the component API Endpoint. Performing a manipulation results in dynamically-determined object attributes. This vulnerability is known as CVE-2026-42861. Remote exploitation of the attack is possible. Furthermore, an exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in FlowiseAI Flowise up to 3.0.12. It has been classified as critical. This affects the function createLead of the component API Endpoint. The manipulation with an unknown input leads to a dynamically-determined object attributes vulnerability. CWE is classifying the issue as CWE-915. The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to version 3.1.2, a mass assignment vulnerability exists in the variable update endpoint of FlowiseAI. The endpoint allows authenticated users to modify server-controlled properties such as workspaceId, createdDate, and updatedDate when updating a variable resource. Due to missing server-side validation and authorization checks, an attacker can manipulate the workspaceId field and reassign variables to arbitrary workspaces. This behavior may break tenant isolation in multi-workspace environments. This issue has been patched in version 3.1.2.

It is possible to read the advisory at gist.github.com. This vulnerability is uniquely identified as CVE-2026-42861. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details and a public exploit are known.

The exploit is shared for download at gist.github.com. It is declared as proof-of-concept.

Upgrading to version 3.1.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1554). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Open Source Flowise

Productinfo

Vendor

• FlowiseAI

Name

• Flowise

Version

• 3.0.0
• 3.0.1
• 3.0.2
• 3.0.3
• 3.0.4
• 3.0.5
• 3.0.6
• 3.0.7
• 3.0.8
• 3.0.9
• 3.0.10
• 3.0.11
• 3.0.12

CPE 2.3info

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CPE 2.2info

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• 🔒
• 🔒

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Threat Intelligenceinfo

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Submitinfo

Accepted

• Submit #777658: FlowiseAI Flowise <= 3.0.12 Improperly Controlled Modification of Dynamically-Determined Object Attributes (CWE-915) (by Eric-a)

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

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