Missing Authentication for Critical Function Affecting lfx package, versions [,0.4.2)
Threat Intelligence
This vulnerability is trending on Twitter; this may indicate a growing threat.
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-PYTHON-LFX-17400159
- published22 Jun 2026
- disclosed17 Jun 2026
- creditOri Lahav
Introduced: 17 Jun 2026
NewCVE-2026-55450 (opens in a new tab)How to fix?
Upgrade lfx to version 0.4.2 or higher.
Overview
lfx is a lfx is a command-line tool for running Langflow workflows. It provides two main commands: serve and run.
Affected versions of this package are vulnerable to Missing Authentication for Critical Function via the create_upload_file function. An attacker can exhaust server disk space and obtain sensitive file system information by uploading arbitrary files without authentication and receiving absolute file paths in the response.