Missing Authentication for Critical Function The advisory has been revoked - it doesn't affect any version of package langflow (opens in a new tab)
Threat Intelligence
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-LANGFLOW-14858129
- published4 Jan 2026
- disclosed2 Jan 2026
- creditKyungJoon Park
Introduced: 2 Jan 2026
CVE-2026-21445 (opens in a new tab)Amendment
This was deemed not a vulnerability.
Overview
langflow is an A Python package with a built-in web application
Affected versions of this package are vulnerable to Missing Authentication for Critical Function on the critical API endpoints messages, transactions, and session, handling sensitive user data and system operations. An unauthenticated attacker can access confidential conversation data and transaction histories, and perform destructive actions such as deleting messages.