What is CVE-2026-18904?

CVE-2026-18904 is a high-severity vulnerability in IBM Langflow Oss, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.2/10. Published 2026-08-28.

How severe is CVE-2026-18904?

High severity. CVSS v3 base score is 8.2 out of 10.

Auth bypass in IBM Langflow Oss

CVE-2026-18904

IBM Langflow OSS 1.0.0 through 1.11.1 could allow a remote attacker to obtain sensitive information and inject unauthorized messages due to a namespace collision between user identifiers.

Vulnerability class: IDOR (Insecure Direct Object Reference)

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.

Affected products

Ibm Langflow Oss

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

psirt@us.ibm.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-18904?: CVE-2026-18904 is a high-severity vulnerability in IBM Langflow Oss, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.2/10. Published 2026-08-28.
How severe is CVE-2026-18904?: High severity. CVSS v3 base score is 8.2 out of 10.