CVE-2026-34046
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.
- CVSS 4.0
- 8.7
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.8
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 40% of CVEs (scores of 2026-10-26)
- CWEs
- CWE-639, CWE-862
- Published
- Modified
- Record from
- the NVD, synced
Affected
- langflow:langflow
- langflow:langflow-base
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-8c4j-f57c-35cf | PyPI | langflow | <1.5.1 | 1.5.1 |
| GHSA-8c4j-f57c-35cf | PyPI | langflow-base | <0.5.1 | 0.5.1 |
| PYSEC-2026-2567 | PyPI | langflow | <1.5.1 | 1.5.1 |
| PYSEC-2026-2570 | PyPI | langflow-base | <0.5.1 | 0.5.1 |