CVE-2026-42867

Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint

At a glance

Severity: MEDIUM 6.5
EPSS: EPSS 0.47 % · percentile 40 (2026-10-27)
State: PUBLISHED
Published: 2026-06-23
Updated: 2026-06-23
Assigner: GitHub_M
NVD status: Analyzed

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 (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.

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L	GitHub_M
CVSS 3.1	MEDIUM 6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L	NVD · security-advisories@github.com (Secondary)

Weaknesses (CWE)

CWE-22

Advisories

GHSA-79ph-745m-6wxq — Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint
PYSEC-2026-2566 — Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint

European references

ENISA EUVD · EUVD-2026-38518
GCVE · GCVE-0-2026-42867

Affected configurations (NVD CPE)

cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* < 1.9.0

Affected products

Product	Versions
langflow-ai · langflow	affected < 1.9.0

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD