CVE-2026-55450: critical vulnerability in langflow-ai langflow
Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak
Published
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85Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 9.3epss 1.2%
from disclosure to weapon111 days
Published on NVDJun 23
1st PoC+111d
VulnCheck+47d
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H
Affected products
langflow-ai · langflowpublic PoCs found — 1
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Related CVEs — langflow-ai langflow
In the same product, most dangerous first.
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