Is CVE-2026-55450 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55450 being exploited in the wild.

How severe is CVE-2026-55450?

Critical severity, with a CVSS score of 9.3, published 23 June 2026.

Which products and versions are affected?

langflow (PyPI) ECOSYSTEM:introduced=0,fixed=1.9.1.

Is there a fix for CVE-2026-55450?

Yes. langflow (PyPI): upgrade to 1.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55450 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-55450?

Check whether you run langflow (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55450: Langflow unauthenticated file upload and path disclosure in upload endpoint

CVE-2026-55450 · Severity: critical · CVSS 9.3 · Published 2026-06-23

Langflow, a tool for building AI-powered workflows, contained a security flaw in a deprecated file upload feature. An unauthorized person could upload unlimited amounts of data to the server, potentially crashing the system by filling up its storage space. Additionally, the system would reveal the exact location of files on the server's hard drive, which could help an attacker plan further intrusions.

Technologies: langflow (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-55450 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55450 being exploited in the wild.
How severe is CVE-2026-55450?: Critical severity, with a CVSS score of 9.3, published 23 June 2026.
Which products and versions are affected?: langflow (PyPI) ECOSYSTEM:introduced=0,fixed=1.9.1.
Is there a fix for CVE-2026-55450?: Yes. langflow (PyPI): upgrade to 1.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55450 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-55450?: Check whether you run langflow (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

langflow (PyPI): upgrade to 1.9.1 or later
```
pip install "langflow>=1.9.1"
```

Technical details

A deprecated endpoint, POST /api/v1/upload/{flow_id}, lacked authentication and authorization checks (CWE-306). An unauthenticated attacker could send arbitrary data to this endpoint, which would be saved to the local filesystem without size limitations, leading to uncontrolled resource consumption (CWE-400) and potential Denial of Service (DoS). Furthermore, the API response included the absolute path of the uploaded file on the server, resulting in sensitive information disclosure (CWE-200). The vulnerability was addressed in version 1.9.1 by applying the 'get_flow' dependency to the route, which enforces both user authentication and flow-ownership verification.

Affected products

langflow-ai Langflow < 1.9.1

Identifiers

CVE-2026-55450
GHSA-x223-p2gf-v735
PYSEC-2026-224

Timeline

2026-04-22: patched: Fix merged in Pull Request #12831
2026-06-17: advisory: GitHub Security Advisory GHSA-x223-p2gf-v735 published
2026-06-23: disclosed: CVE-2026-55450 published to NVD

References

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