Medium
Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint
Type: advisorySources: OSV
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 (POST /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are used directly to create file paths without proper sanitization or containment checks. An authenticated attacker can exploit this flaw to create directories and write files anywhere on the server's filesystem. This vulnerability is fixed in 1.9.0.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-42867
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 02:04 UTC · Revision 1
Source evidence
Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint
core-osv · Original sourcePublished 23 Jun 2026, 16:29 UTC
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 (POST /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are used directly to create file paths without proper sanitization or containment checks. An authenticated attacker can exploit this flaw to create directories and write files anywhere on the server's filesystem. This vulnerability is fixed in 1.9.0.
osv:CVE-2026-42867
Complete source record
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"url": "https://osv.dev/vulnerability/CVE-2026-42867",
"method": "structured",
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"title": "Langflow: Path Traversal in Knowledge Bases API via Creation Endpoint",
"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 (POST /api/v1/knowledge_bases). This occurs because user-supplied knowledge base names are used directly to create file paths without proper sanitization or containment checks. An authenticated attacker can exploit this flaw to create directories and write files anywhere on the server's filesystem. This vulnerability is fixed in 1.9.0.",
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"modified": "2026-10-28T02:30:32.342808789Z",
"provider": "osv",
"references": [
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"https://github.com/langflow-ai/langflow/security/advisories/GHSA-79ph-745m-6wxq",
"https://nvd.nist.gov/vuln/detail/CVE-2026-42867",
"https://github.com/langflow-ai/langflow/pull/12337"
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"source_id": "core-osv",
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"published_at": "2026-06-23T16:29:11.848+00:00"
}