CVE-2026-55450

Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak

State: Published
Severity: 9.3 Critical
Published: Jun 23, 2026
Updated: Jun 23, 2026
Reserved: Jun 16, 2026

Description

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1.

Scores

CVSS	Score	Vector	Source
3.1	9.3 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H	GitHub_M

Weaknesses

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-306 Missing Authentication for Critical Function
CWE-400 Uncontrolled Resource Consumption

Affected Products

Product	Versions
langflowlangflow-ai	< 1.9.1Affected

References

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