Path traversal in Langflow - CVE-2026-42867
Published: June 12, 2026
Vulnerability identifier: #VU134432
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-42867
CWE-ID: CWE-22
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Langflow
Affected software:
Langflow
Langflow
Detailed vulnerability description
The vulnerability allows a remote attacker to create directories and write files outside the intended directory.
The vulnerability exists due to path traversal in the create_knowledge_base function within the Knowledge Bases API when handling crafted knowledge base names in POST /api/v1/knowledge_bases requests. A remote attacker can send a specially crafted request with traversal sequences or an absolute path to create directories and write files outside the intended directory.
The issue affects filesystem operations for embedding_metadata.json and schema.json written to the attacker-controlled path.
How to mitigate CVE-2026-42867
Install security update from vendor's website.