# CVE-2026-55450: Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak


- **Severity:** Critical 9.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Jun 2026
- **Updated:** 23 Jun 2026
- **Also known as:** GHSA-x223-p2gf-v735, PYSEC-2026-224

## What is CVE-2026-55450?

CVE-2026-55450 is a critical vulnerability in Langflow Langflow, published on 23 Jun 2026. 

### Official 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.

Weakness: CWE-400 (Uncontrolled Resource Consumption), CWE-306 (Missing Authentication for Critical Functionality), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-55450?

3 open source packages ship an affected version, including langflow. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `langflow` | PyPI | All versions | 1.9.1 |
| `langflow` | PyPI | All versions | 1.9.1 |
| `langflow` | PyPI | All versions | 1.9.1 |

Products: Langflow Langflow.

## How do I fix CVE-2026-55450?

Upgrade langflow to 1.9.1 or later.

## Is CVE-2026-55450 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55450 exists.

Public exploit code:

- CVE-2026-55450 (github_poc): https://github.com/0xredash/CVE-2026-55450
- Langflow < 1.9.1 - Unauthenticated File Upload (nuclei): http/cves/2026/CVE-2026-55450.yaml

## Other vulnerabilities in Langflow Langflow

- [CVE-2026-9198](https://insights.sbomify.com/CVE-2026-9198/): IBM Langflow Code Injection (critical 9.8, exploited in the wild)
- [CVE-2026-0770](https://insights.sbomify.com/CVE-2026-0770/): Langflow Inclusion of Functionality from Untrusted Control Sphere (critical 9.8, exploited in the wild)
- [CVE-2025-3248](https://insights.sbomify.com/CVE-2025-3248/): Langflow Missing Authentication (critical 9.8, exploited in the wild)
- [CVE-2025-34291](https://insights.sbomify.com/CVE-2025-34291/): Langflow Origin Validation Error (critical 9.4, exploited in the wild)
- [CVE-2026-33017](https://insights.sbomify.com/CVE-2026-33017/): Langflow Code Injection (critical 9.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55450 and fix it if it is affected.

What it is: CVE-2026-55450 is a critical vulnerability in Langflow Langflow, published on 23 Jun 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55450 exists.

Affected packages and fixed versions:
- langflow (PyPI): affected all versions; fixed in 1.9.1
- langflow (PyPI): affected all versions; fixed in 1.9.1
- langflow (PyPI): affected all versions; fixed in 1.9.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-55450/ (Markdown: https://insights.sbomify.com/CVE-2026-55450/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55450
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55450
- OSV: https://osv.dev/vulnerability/CVE-2026-55450

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55450/
Summaries are generated and may contain mistakes; the official description above is the record.