CVE-2026-42867CWE-22

Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint

Medium · published June 23, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
39.4
In the wild
Unconfirmed
What it is

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 (POST /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are used directly to create file paths without proper sanitization or containment checks. An authenticated attacker can exploit this flaw to create directories and write files anywhere on the server's filesystem. This vulnerability is fixed in 1.9.0.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00466 · 39.4th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-06-23T16:29Z
EPSS history
Timeline
  • 23 JUN 16:29Z
    Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint
    cvelistv5