Skip to content
EXYS
Back to the CVEs

CVE-2026-55255

8.4, high Known exploited

Langflow Authorization Bypass Through User-Controlled Key Vulnerability

NVD (opens in a new tab) CVE.org (opens in a new tab) CISA KEV catalogue (opens in a new tab)
CVSS
8.4, high high CVSS v3.1
EPSS, next 30 days
0.9% higher than 58.5% of scored CVEs
Exploitation
Confirmed in the wild
Published
23 Jun 20263 months ago

Known exploited

CISA added this to the Known Exploited Vulnerabilities Catalog on 7 Jul 2026. US federal agencies had to remediate by 10 Jul 2026, a deadline that has passed.

Required action. Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Description

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.1.

Details

Vendor
Langflow
Product
langflow
Weakness
CWE-639 (opens in a new tab)
Status
Analyzed
Updated
7 Oct 2026
Assigner
security-advisories@github.com

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L

References 5

Exploit code 1

Patches and fixes 2

Advisories 1

Other references 1

The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.

Other Langflow CVEs

Every Langflow CVE we hold

Same vendor in what we hold, not a known link between the flaws.

  • CVE-2026-33017 Langflow Code Injection Vulnerability KEV EPSS 25% 9.8, critical
  • CVE-2026-0770 Langflow Inclusion of Functionality from Untrusted Control Sphere Vulnerability KEV EPSS 63% 9.8, critical
  • CVE-2025-34291 Langflow Origin Validation Error Vulnerability KEV EPSS 93% 8.8, high
  • CVE-2025-3248 Langflow Missing Authentication Vulnerability KEV EPSS 100% 9.8, critical

Beyond this page

Is CVE-2026-55255 in your network?

This page tells you how dangerous CVE-2026-55255 is out there. Whether it sits on one of your devices, only a scan of your own network can tell. That is what our systems do, every day, for the companies we protect.

CVE-2026-55255 is in the CISA catalogue of exploited vulnerabilities: attackers are already exploiting it.

  • EXYS7600 OCELOT

    Find it before attackers do

    Ocelot scans your network on a schedule and reports every vulnerability it finds by its CVE identifier, with its CVSS score and how many of your hosts are affected. A finding like CVE-2026-55255 comes with the devices to patch.

    Learn more about EXYS7600 OCELOT

  • EXYS7950 KONDRA

    Detect it if it's exploited

    Until the patch is applied, Kondra monitors your network, events and endpoints in real time. It keeps an inventory of the software installed on every endpoint, and its anomaly detection rules flag what an attacker does once inside.

    Learn more about EXYS7950 KONDRA
Check your exposure

Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 17 Oct 2026, not the live upstream state.