Authorization bypass through user-controlled key in Langflow - CVE-2026-105699
Published: October 16, 2026
Vulnerability identifier: #VU156087
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-105699
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to read other users' flow-backed files and disclose sensitive information across project boundaries.
The vulnerability exists due to missing ownership and project-membership checks in Langflow's MCP handle_read_resource() function when processing resource URIs supplied through resources/read. A remote user can connect to a project-scoped MCP endpoint they own and submit a file-download URI containing another user's flow ID and filename to retrieve the corresponding file without authorization.
Affected software
Langflow
How to mitigate CVE-2026-105699
Install security update from vendor's website.
Langflow - update to 1.9.1