PYSEC-2026-2570

See a problem?
Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/langflow-base/PYSEC-2026-2570.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-2570
Aliases
Published
2026-07-13T14:36:45.537461Z
Modified
2026-07-13T16:43:44.480752312Z
Severity
  • 8.7 (High) CVSS_V4 - 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 Calculator
Summary
Langflow: Authenticated Users Can Read, Modify, and Delete Any Flow via Missing Ownership Check
Details

Vulnerability

IDOR in GET/PATCH/DELETE /api/v1/flow/{flow_id}

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 exposed any authenticated user to:

  • Read any other user's flow, including embedded plaintext API keys
  • Modify the logic of another user's AI agents
  • 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.

Fix (PR #8956)

The fix removes the AUTO_LOGIN conditional entirely and unconditionally scopes the query to the requesting user:

-    auth_settings = settings_service.auth_settings
-    stmt = select(Flow).where(Flow.id == flow_id)
-    if auth_settings.AUTO_LOGIN:
-        stmt = stmt.where(
-            (Flow.user_id == user_id) | (Flow.user_id == None)  # noqa: E711
-        )
+    stmt = select(Flow).where(Flow.id == flow_id).where(Flow.user_id == user_id)

All three operations — read, update, and delete — route through _read_flow, so the single change covers the full attack surface. A cross-user isolation test (test_read_flows_user_isolation) was added to prevent regression.

Acknowledgements

Langflow thanks the security researcher who responsibly disclosed this vulnerability:

References

Affected packages

PyPI / langflow-base

Package

Name
langflow-base
View open source insights on deps.dev
Purl
pkg:pypi/langflow-base

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
0.5.1

Affected versions

0.*
0.0.13
0.0.14
0.0.15
0.0.16
0.0.17
0.0.18
0.0.19
0.0.20
0.0.21
0.0.22
0.0.23
0.0.24
0.0.25
0.0.26
0.0.27
0.0.28
0.0.29
0.0.30
0.0.31
0.0.32
0.0.33
0.0.34
0.0.35
0.0.36
0.0.37
0.0.38
0.0.39
0.0.40
0.0.41
0.0.42
0.0.43
0.0.44
0.0.45
0.0.46
0.0.47
0.0.48
0.0.49
0.0.50
0.0.51
0.0.52
0.0.53
0.0.54
0.0.55
0.0.56
0.0.57
0.0.58
0.0.59
0.0.60
0.0.61
0.0.62
0.0.63
0.0.64
0.0.66
0.0.67
0.0.68
0.0.69
0.0.70
0.0.71
0.0.72
0.0.73
0.0.74
0.0.75
0.0.76
0.0.77
0.0.78
0.0.79
0.0.80
0.0.81
0.0.82
0.0.83
0.0.84
0.0.85
0.0.86
0.0.87
0.0.88
0.0.89
0.0.90
0.0.91
0.0.92
0.0.93
0.0.94
0.0.95
0.0.96
0.0.97
0.0.98
0.0.99
0.1.0
0.1.1
0.1.2
0.1.3
0.1.4
0.1.4.post1
0.2.0
0.3.0
0.3.1
0.3.2
0.3.3
0.3.4
0.4.0
0.4.1
0.4.2
0.4.3
0.5.0
0.5.0.post1
0.5.0.post2

Database specific

source 
"https://github.com/pypa/advisory-database/blob/main/vulns/langflow-base/PYSEC-2026-2570.yaml"