What is CVE-2026-55255?

CVE-2026-55255 is a critical-severity vulnerability in Langflow-ai Langflow, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 9.9/10. Published 2026-06-23.

How severe is CVE-2026-55255?

Critical severity. CVSS v3 base score is 9.9 out of 10.

Auth bypass in Langflow-ai Langflow

CVE-2026-55255

Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.2, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belo…

Vulnerability class: IDOR (Insecure Direct Object Reference)

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L.

Affected products

Langflow-ai Langflow — versions < 1.9.2

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-55255?: CVE-2026-55255 is a critical-severity vulnerability in Langflow-ai Langflow, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 9.9/10. Published 2026-06-23.
How severe is CVE-2026-55255?: Critical severity. CVSS v3 base score is 9.9 out of 10.