Is CVE-2026-55255 exploited in the wild?

Yes. CVE-2026-55255 is known to be exploited in the wild, first recorded on 7 July 2026. Treat it as urgent.

How severe is CVE-2026-55255?

Critical severity, with a CVSS score of 9.9, published 23 June 2026.

Which products and versions are affected?

langflow (PyPI) ECOSYSTEM:introduced=0,fixed=1.9.1, ECOSYSTEM:introduced=0,fixed=1.9.2.

Is there a fix for CVE-2026-55255?

Yes. langflow (PyPI): upgrade to 1.9.1, 1.9.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55255 attacked?

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

Am I affected by CVE-2026-55255?

Check whether you run Langflow or 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-2026-55255: Langflow IDOR in responses endpoint allows cross-user flow execution

CVE-2026-55255 · Severity: critical · CVSS 9.9 · Exploited in the wild · Published 2026-06-23

Langflow, a platform for building and deploying AI-powered agents, contains a security flaw that allows one user to access and run AI workflows belonging to others. By simply providing the identification number of another user's workflow, an attacker can execute unauthorized tasks, potentially leading to data theft or unauthorized use of AI resources. This issue poses a significant risk to the privacy and integrity of automated business processes.

Technologies: Langflow, langflow (PyPI). Vendors: Langflow, PyPI.

Quick answers

Is CVE-2026-55255 exploited in the wild?: Yes. CVE-2026-55255 is known to be exploited in the wild, first recorded on 7 July 2026. Treat it as urgent.
How severe is CVE-2026-55255?: Critical severity, with a CVSS score of 9.9, published 23 June 2026.
Which products and versions are affected?: langflow (PyPI) ECOSYSTEM:introduced=0,fixed=1.9.1, ECOSYSTEM:introduced=0,fixed=1.9.2.
Is there a fix for CVE-2026-55255?: Yes. langflow (PyPI): upgrade to 1.9.1, 1.9.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55255 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-55255?: Check whether you run Langflow or 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, 1.9.2 or later
```
pip install "langflow>=1.9.2"
```

Technical details

An Insecure Direct Object Reference (IDOR) vulnerability exists in the Langflow /api/v1/responses endpoint. The application fails to properly validate that the authenticated user requesting a flow execution has the appropriate permissions for the specified flow ID. An attacker with valid credentials can exploit this by submitting a request containing a victim's flow ID, leading to unauthorized execution of arbitrary AI workflows. This vulnerability is classified as CWE-639 (Authorization Bypass Through User-Controlled Key) and has been addressed in version 1.9.2.

Affected products

Langflow AI Langflow < 1.9.2

Identifiers

CVE-2026-55255
GHSA-qrpv-q767-xqq2
PYSEC-2026-221

Timeline

2026-06-23: advisory: Original GitHub security advisory published
2026-06-23: disclosed: CVE-2026-55255 published to NVD
2026-07-07: other: Advisory publication date provided in report

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