CVE-2026-55450
Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1.
INFO
Published Date :
June 23, 2026, 5:17 p.m.
Last Modified :
June 24, 2026, 1:50 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 | CRITICAL | [email protected] |
Solution
- Update Langflow to version 1.9.1 or later.
- Restrict file upload permissions.
- Monitor server storage usage.
Public PoC/Exploit Available at Github
CVE-2026-55450 has a 3 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2026-55450.
| URL | Resource |
|---|---|
| https://github.com/langflow-ai/langflow/pull/12831 | Issue Tracking Patch |
| https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735 | Exploit Patch Vendor Advisory |
| https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735 | Exploit Patch 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-2026-55450 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-2026-55450
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).
Read-only Linux host checker for supply-chain incident response, including vulnerable kernel posture, risky module state, and known developer-tooling persistence indicators
JavaScript PowerShell
Here We Go Again” is an active npm/PyPI supply-chain worm, not just a credential stealer.
JavaScript
Read-only exposure scanner and recovery guide for the May 2026 TanStack npm supply-chain incident. Detects known indicators without executing package code.
JavaScript
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55450 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-55450 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. 24, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* versions up to (excluding) 1.9.1 Added Reference Type GitHub, Inc.: https://github.com/langflow-ai/langflow/pull/12831 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735 Types: Exploit, Patch, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735 Types: Exploit, Patch, 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-x223-p2gf-v735 Added SSVC {'id': 'CVE-2026-55450', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-23T17:00:33.147977Z'} -
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': '< 1.9.1'}]}] Added Description Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H Added CWE CWE-200 Added CWE CWE-400 Added CWE CWE-306 Added Reference https://github.com/langflow-ai/langflow/pull/12831 Added Reference https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735