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OpenAdvisories
Medium · 6.5 CVE-2026-9186 EUVD-2026-71215GHSA-gqfh-c8pj-64mr

Langflow is vulnerable to stored cross-site scripting and IP spoofing due to unsanitized Markdown rendering and untrusted proxy header trust

Published Sep 4, 2026 · Updated Sep 8, 2026 · Assigned by ibm

Vendor: IBM Product: Langflow OSS

Description

IBM Langflow OSS 1.0.0 through 1.11.2 allows remote authenticated attackers to bypass localhost-only MCP configuration installation by spoofing X-Forwarded-For: 127.0.0.1 header, enabling arbitrary writes to IDE config files (~/.cursor/mcp.json, etc.).

Affected products

VendorProductAffectedFixed
IBM Langflow OSS 1.0.0 – ≤ 1.11.2 —

Advisories 1

References