Vulnerability · Published May 12, 2026 · Assigned by GitHub_M

CVE-2026-42048Langflow: Path Traversal in Langflow Knowledge Bases API

Critical 9.6

In plain English

A critical-severity path traversal in langflow from langflow-ai. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 4.2% (higher than 91% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.6Critical

Exploit odds (30 days)4.2%top 9.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack tooling1Public PoC

Official description

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, Langflow is vulnerable to Path Traversal in the Knowledge Bases API (DELETE /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are concatenated directly into file paths without proper sanitization or boundary validation. An authenticated attacker can exploit this flaw to delete arbitrary directories anywhere on the server's filesystem, leading to data loss and potential service disruption. This vulnerability is fixed in 1.9.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	langflow	1.9.0	GHSA-9whx-c884-c68q
PyPI	langflow	1.9.0	PYSEC-2026-377

Affected products (as reported)

Vendor	Product	Versions
langflow-ai	langflow	< 1.9.0

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H

References

https://github.com/langflow-ai/langflow/security/advisories/GHSA-9whx-c884-c68q x_refsource_CONFIRM