CVE-2026-7663 PUBLISHED

Unauthenticated Cross-User MCP Resource Access and Tool Execution via Streamable Transport Authorization Bypass

Assigner: ibm
Reserved: 01.05.2026 Published: 30.06.2026 Updated: 01.07.2026

IBM Langflow OSS 1.0.0 through 1.9.6 could allow unauthenticated attackers to access protected MCP project resources and execute MCP operations due to improper authorization enforcement in the Streamable MCP transport endpoint.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS Score: 9.1

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	IBM
Product	Langflow OSS
Versions	affected from 1.0.0 to 1.9.6 (incl.)

Solutions

IBM strongly recommends addressing the vulnerability now by upgrading Langflow OSS to version 1.10.0 https://pypi.org/project/langflow/

References

https://www.ibm.com/support/pages/node/7277570

Problem Types

CWE-285 Improper Authorization CWE