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
langflow: langflow; apple: macos; linux: linux kernel; microsoft: windows
References1
- www.ibm.com/support/pages/node/7285646 PatchVendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 32 · as of 4 November 2026
- CWE
- CWE-284
Could this be exploited in your environment?
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