Auth bypass in Langflow
CVE-2026-55450
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.
Vulnerability class: Information Disclosure
EPSS: 0.012 (66.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H.
Affected products
- Langflow
- Langflow-ai Langflow — versions < 1.9.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Patch, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
Frequently asked questions
- What is CVE-2026-55450?
- CVE-2026-55450 is a critical-severity vulnerability in Langflow, classified under Information Disclosure. CVSS score: 9.3/10. Published 2026-06-23.
- How severe is CVE-2026-55450?
- Critical severity. CVSS v3 base score is 9.3 out of 10.