CVE-2026-34046
Severity CVSS v4.0:
HIGH
Type:
Unavailable / Other
Publication date:
27/03/2026
Last modified:
11/05/2026
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to version 1.5.1, the `_read_flow` helper in `src/backend/base/langflow/api/v1/flows.py` branched on the `AUTO_LOGIN` setting to decide whether to filter by `user_id`. When `AUTO_LOGIN` was `False` (i.e., authentication was enabled), neither branch enforced an ownership check — the query returned any flow matching the given UUID regardless of who owned it. This allowed any authenticated user to read any other user's flow, including embedded plaintext API keys; modify the logic of another user's AI agents, and/or delete flows belonging to other users. The vulnerability was introduced by the conditional logic that was meant to accommodate public/example flows (those with `user_id = NULL`) under auto-login mode, but inadvertently left the authenticated path without an ownership filter. The fix in version 1.5.1 removes the `AUTO_LOGIN` conditional entirely and unconditionally scopes the query to the requesting user.
Impact
Base Score 4.0
8.70
Severity 4.0
HIGH
Base Score 3.x
8.80
Severity 3.x
HIGH
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* | 1.5.0 (excluding) | |
| cpe:2.3:a:langflow:langflow:1.5.0:dev0:*:*:*:*:*:* | ||
| cpe:2.3:a:langflow:langflow:1.5.0:dev1:*:*:*:*:*:* | ||
| cpe:2.3:a:langflow:langflow-base:*:*:*:*:*:python:*:* | 0.5.1 (excluding) |
To consult the complete list of CPE names with products and versions, see this page