Critical
Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak
Type: advisorySources: OSV
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-55450
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 04:00 UTC · Revision 1
Source evidence
Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak
core-osv · Original sourcePublished 23 Jun 2026, 16:17 UTC
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1.
osv:CVE-2026-55450
Complete source record
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"url": "https://osv.dev/vulnerability/CVE-2026-55450",
"method": "structured",
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"title": "Langflow: Unauthenticated file upload leads to DoS (space exhaustion) and information leak",
"summary": "Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, unauthenticated users can upload any amount of data to the server without any limitations. No need for any prior knowledge, only network access to Langflow. This can lead to space exhaustion on the server. In addition, in the response, the absolute path of the uploaded file is reported to the attacker, which is an information leak that can assist in chaining other primitives. This vulnerability is fixed in 1.9.1.",
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"modified": "2026-10-28T02:30:33.025776258Z",
"provider": "osv",
"references": [
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"https://github.com/langflow-ai/langflow/security/advisories/GHSA-x223-p2gf-v735",
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"source_id": "core-osv",
"document_id": 500198,
"published_at": "2026-06-23T16:17:52.168+00:00"
}