CVE-2026-123271
ChatCLI before v1.215.2 Origin Validation Error via Unvalidated MCP OAuth Resource Indicator
ChatCLI before v1.215.2 contains an improper validation vulnerability in the MCP OAuth login flow that uses server-supplied Protected Resource Metadata as the resource indicator without checking it matches the configured server URL. A malicious MCP server can declare another resource on the same authorization server, obtain the user's bearer token for it, and replay that token against the other resource.
CVSS 4.0 · 5.1 Medium
EPSS < 1%
KEV · Not listed
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