CVE-2026-5027: Langflow - Path Traversal Arbitrary File Write via upload_user_file

Published Mar 27, 2026
·
Updated

The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').

Affected Software

2 affected components
Langflow Langflow
Langflow Langflow<1.9.0

Event History

Mar 27, 2026
CVE Published
via MITRE·02:54 PM
Data Sourced
via MITRE·02:54 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:17 PM
DescriptionSeverityWeaknessAffected Software
Jun 10, 2026
News Published
via BleepingComputer·09:23 PM
News Published
via BleepingComputer·09:24 PM
Jul 8, 2026
News Published
via BleepingComputer·09:58 AM

Frequently Asked Questions

1

What is the severity of CVE-2026-5027?

CVE-2026-5027 is categorized as a high-severity vulnerability due to its potential for arbitrary file write exploitation.

2

How do I fix CVE-2026-5027?

To fix CVE-2026-5027, ensure that the 'filename' parameter is properly sanitized to prevent path traversal attacks.

3

What kind of attack does CVE-2026-5027 allow?

CVE-2026-5027 allows an attacker to conduct path traversal attacks that enable arbitrary file writes on the server's filesystem.

4

Which endpoint is affected by CVE-2026-5027?

The vulnerability CVE-2026-5027 affects the 'POST /api/v2/files' endpoint.

5

What software is affected by CVE-2026-5027?

CVE-2026-5027 affects the Langflow software, particularly through its file upload feature.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203