CVE-2026-42867
Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint
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.
INFO
Published Date :
June 23, 2026, 5:16 p.m.
Last Modified :
June 26, 2026, 5:09 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Langflow to version 1.9.0 or later.
- Apply vendor-provided patches if available.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42867.
| URL | Resource |
|---|---|
| https://github.com/langflow-ai/langflow/pull/12337 | Patch Issue Tracking |
| https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq | Exploit Vendor Advisory |
| https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42867 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42867
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42867 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-42867 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 26, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* versions up to (excluding) 1.9.0 Added Reference Type GitHub, Inc.: https://github.com/langflow-ai/langflow/pull/12337 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq Types: Exploit, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 23, 2026
Action Type Old Value New Value Added Reference https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq Added SSVC {'id': 'CVE-2026-42867', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-23T17:01:29.364041Z'} -
New CVE Received by [email protected]
Jun. 23, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'langflow-ai', 'product': 'langflow', 'versions': [{'status': 'affected', 'version': '< 1.9.0'}]}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L Added CWE CWE-22 Added Reference https://github.com/langflow-ai/langflow/pull/12337 Added Reference https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq