CVE-2026-55446 - Vulnerability Details - OpenCVE

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.0.19, an attacker can send a /api/v1/files/upload/ request without any authentication token/cookies and abuse a very long multipart form boundary to make the langflow app unusable for all users for an indefinite amount of time. This vulnerability is fixed in 1.0.19.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation poc

Automatable yes

Technical Impact partial

Vendors	Products
Langflow	Langflow

No data.

No data.

References

Link	Providers
https://github.com/langflow-ai/langflow/pull/3923
https://github.com/langflow-ai/langflow/security/advisories/GHSA-qwqc-p3q8-wcg9

History

Wed, 24 Jun 2026 16:15:00 +0000

Type	Values Removed	Values Added
First Time appeared		Langflow Langflow langflow
Vendors & Products		Langflow Langflow langflow

Tue, 23 Jun 2026 18:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Tue, 23 Jun 2026 16:45:00 +0000

Type	Values Removed	Values Added
Description		Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.0.19, an attacker can send a /api/v1/files/upload/ request without any authentication token/cookies and abuse a very long multipart form boundary to make the langflow app unusable for all users for an indefinite amount of time. This vulnerability is fixed in 1.0.19.
Title		Langflow: Unauthenticated DoS through multipart form boundary file upload
Weaknesses		CWE-400
References		https://github.com/langflow-ai/langflow/pull/3923 https://github.com/langflow-ai/langflow/security/advisories/GHSA-qwqc-p3q8-wcg9
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}`

MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-06-23T16:26:17.990Z

Updated: 2026-06-23T17:56:37.766Z

Reserved: 2026-06-16T21:59:57.018Z

Link: CVE-2026-55446

Vulnrichment

Updated: 2026-06-23T17:56:26.114Z

NVD

No data.

Redhat

No data.

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