CVE-2026-42048 json
Langflow: Path Traversal in Langflow Knowledge Bases API
published 6mo ago modified 3mo ago also EUVD-2026-29700 , GHSA-9whx-c884-c68q , PYSEC-2026-377
- cvss
- 9.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.2%
- EPSS 4.2% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, 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. This vulnerability is fixed in 1.9.0.
Patch / fix
- pypi langflow 1.9.0
- langflow langflow 1.9.0
- langflow-ai langflow 1.9.0
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
4.20% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/langflow-ai/langflow/security/advisories/GHSA-9whx-c884-c68q referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H |
| GitHub | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H |
| OSV | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | langflow | <1.9.0 |
1.9.0 |
Affected products
- langflow-ai langflow
Classification
- Weakness
-
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory
References
-
github.com
/langflow-ai/langflow/security/advisories/GHSA-9whx-c884-c68q
exploit, web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-42048
advisory
-
github.com
/langflow-ai/langflow
package
-
pypi.org
/project/langflow
package
-
github.com
/advisories/GHSA-9whx-c884-c68q
advisory
Sources
- CVE List CVE-2026-42048
- GitHub Advisory GHSA-9whx-c884-c68q
- NVD CVE-2026-42048
- OSV PYSEC-2026-377
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.