GHSA-9whx-c884-c68q

Suggest an improvement
Source
https://github.com/advisories/GHSA-9whx-c884-c68q
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-9whx-c884-c68q/GHSA-9whx-c884-c68q.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-9whx-c884-c68q
Aliases
  • CVE-2026-42048
Published
2026-05-05T18:28:59Z
Modified
2026-05-13T16:38:40.621226Z
Severity
  • 9.6 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H CVSS Calculator
Summary
Langflow Knowledge Bases API is Vulnerable to Path Traversal
Details

Summary

Langflow is vulnerable to Path Traversal in the Knowledge Bases API (DELETE /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are concatenated directly into file paths without proper sanitization or boundary validation. An authenticated attacker can exploit this flaw to delete arbitrary directories anywhere on the server's filesystem, leading to data loss and potential service disruption.

Details

The vulnerability exists in the delete_knowledge_bases_bulk function within src/backend/base/langflow/api/v1/knowledge_bases.py.

This function constructs file paths directly from the user-supplied kb_names parameter. While other knowledge base endpoints safely route through standard path resolution (e.g., _resolve_kb_path()), the bulk delete handler bypasses this entirely. It builds the path manually and passes it directly to shutil.rmtree() without validating if the resulting path resolves outside the intended user directory.

PoC (Proof of Concept)

For the Bulk Delete endpoint, an authenticated attacker can supply a traversal sequence in the kb_names parameter: ../victim_user/kb_name

Because the path is passed directly to shutil.rmtree() without containment checks, this payload deletes directories outside the intended scope.

Impact

Any Langflow instance exposing this endpoint to authenticated users is vulnerable. This exposes the server to: * Cross-user data compromise: Deletion of directories within another tenant's knowledge base space. * Arbitrary filesystem manipulation: Directory deletion at any path on the server where the application has write permissions. * Service disruption & Data Loss: Deletion of critical application files or unrecoverable data loss if backups are co-located on the same filesystem.

Fixes

The issue was addressed in PR #12243, which applies Path.resolve() to normalize the supplied path and validates that it starts with the authenticated user's directory before deletion. Subsequent updates (backported from PR #12337) introduced robust containment checks using Path.is_relative_to() to prevent prefix-ambiguity bugs.

Acknowledgements

Thanks to the security researchers who responsibly disclosed this vulnerability: * @ddlxstudio * @nekros1xx

Database specific 
{
    "github_reviewed_at": "2026-05-05T18:28:59Z",
    "github_reviewed": true,
    "cwe_ids": [
        "CWE-22"
    ],
    "nvd_published_at": "2026-05-12T18:17:23Z",
    "severity": "CRITICAL"
}
References

Affected packages

PyPI / langflow

Package

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

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.9.0

Affected versions

0.*
0.0.31
0.0.32
0.0.33
0.0.40
0.0.44
0.0.45
0.0.46
0.0.52
0.0.53
0.0.54
0.0.55
0.0.56
0.0.57
0.0.58
0.0.61
0.0.62
0.0.63
0.0.64
0.0.65
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
0.0.78
0.0.79
0.0.80
0.0.81
0.0.83
0.0.84
0.0.85
0.0.86
0.0.87
0.0.88
0.0.89
0.1.0
0.1.2
0.1.3
0.1.4
0.1.5
0.1.6
0.1.7
0.2.0
0.2.1
0.2.2
0.2.3
0.2.4
0.2.5
0.2.6
0.2.7
0.2.8
0.2.9
0.2.10
0.2.11
0.2.12
0.2.13
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
0.4.4
0.4.5
0.4.6
0.4.7
0.4.8
0.4.9
0.4.10
0.4.11
0.4.12
0.4.14
0.4.15
0.4.16
0.4.17
0.4.18
0.4.19
0.4.20
0.4.21
0.5.0a0
0.5.0a1
0.5.0a2
0.5.0a3
0.5.0a4
0.5.0a5
0.5.0a6
0.5.0b0
0.5.0b2
0.5.0b3
0.5.0b4
0.5.0b5
0.5.0b6
0.5.0
0.5.1
0.5.2
0.5.3
0.5.4
0.5.5
0.5.6
0.5.7
0.5.8
0.5.9
0.5.10
0.5.11
0.5.12
0.6.0rc1
0.6.0
0.6.1
0.6.2
0.6.3a0
0.6.3a1
0.6.3a2
0.6.3a3
0.6.3a4
0.6.3a5
0.6.3a6
0.6.3a7
0.6.3
0.6.4a0
0.6.4a1
0.6.4
0.6.5a0
0.6.5a1
0.6.5a2
0.6.5a3
0.6.5a4
0.6.5a5
0.6.5a6
0.6.5a7
0.6.5a8
0.6.5a9
0.6.5a10
0.6.5a11
0.6.5a12
0.6.5a13
0.6.5
0.6.6
0.6.7a1
0.6.7a2
0.6.7a3
0.6.7a5
0.6.7
0.6.8
0.6.9
0.6.10
0.6.11
0.6.12
0.6.14
0.6.15
0.6.16
0.6.17
0.6.18
0.6.19
1.*
1.0.0a0
1.0.0a1
1.0.0a2
1.0.0a3
1.0.0a4
1.0.0a5
1.0.0a6
1.0.0a7
1.0.0a8
1.0.0a9
1.0.0a10
1.0.0a11
1.0.0a12
1.0.0a13
1.0.0a14
1.0.0a15
1.0.0a17
1.0.0a18
1.0.0a19
1.0.0a20
1.0.0a21
1.0.0a22
1.0.0a23
1.0.0a24
1.0.0a25
1.0.0a26
1.0.0a27
1.0.0a28
1.0.0a29
1.0.0a30
1.0.0a31
1.0.0a32
1.0.0a33
1.0.0a34
1.0.0a35
1.0.0a36
1.0.0a37
1.0.0a38
1.0.0a39
1.0.0a40
1.0.0a41
1.0.0a42
1.0.0a43
1.0.0a44
1.0.0a45
1.0.0a46
1.0.0a47
1.0.0a48
1.0.0a49
1.0.0a50
1.0.0a51
1.0.0a52
1.0.0a53
1.0.0a55
1.0.0a56
1.0.0a57
1.0.0a58
1.0.0a59
1.0.0a60
1.0.0a61
1.0.0rc0
1.0.0rc1
1.0.0
1.0.1
1.0.2
1.0.3
1.0.4
1.0.5
1.0.6
1.0.7
1.0.8
1.0.9
1.0.10
1.0.11
1.0.12
1.0.13
1.0.14
1.0.15
1.0.16
1.0.17
1.0.18
1.0.19
1.0.19.post1
1.0.19.post2
1.1.0
1.1.1
1.1.2
1.1.3
1.1.4
1.1.4.post1
1.2.0
1.3.0
1.3.1
1.3.2
1.3.3
1.3.4
1.4.0
1.4.1
1.4.2
1.4.3
1.5.0
1.5.0.post1
1.5.0.post2
1.5.1
1.6.0
1.6.1
1.6.2
1.6.3
1.6.4
1.6.5
1.6.6
1.6.7
1.6.8
1.6.9
1.7.0
1.7.1
1.7.2
1.7.3
1.8.0rc0
1.8.0rc1
1.8.0rc2
1.8.0rc3
1.8.0rc4
1.8.0rc5
1.8.0rc6
1.8.0
1.8.1
1.8.2
1.8.3rc0
1.8.3
1.8.4

Database specific

last_known_affected_version_range 
"<= 1.8.4"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-9whx-c884-c68q/GHSA-9whx-c884-c68q.json"