CVE-2026-55255 - Langflow Authorization Bypass Through User-Controlled Key Vulnerability

Technical Severity

CVSS v3.1 Metrics

HIGH

8.4 / 10

Minimal Risk Critical

Vector Specification

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

Exploitation Likelihood

EPSS Prediction

0.89 %

Predictive Probability

Percentile Rank

56.7 th

Documented as more likely to be exploited than 56.7% of known CVEs.

Detection Date

Jul 07, 2026

Remediation Due

Jul 10, 2026

CISA Catalog Active

Threat Analysis

Langflow contains an authorization bypass through user-controlled key vulnerability which allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request.

Remediation Directive

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.

External Intelligence

https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2

CISA

CISA Advisory

https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk

CISA

CISA Advisory

https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk

NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2026-55255