CVE-2026-58497: CWE-346: Origin Validation Error in olo-dot-io Uni-CLI

Uni-CLI, a command interface for various applications, had a security flaw in its legacy JSON-RPC-over-HTTP MCP transport on the local loopback interface. Prior to version 0.225.2, this transport did not validate browser Origin headers before routing requests, allowing malicious web pages to send cross-origin POST requests to the local /mcp endpoint. This could enable attackers to invoke commands on the local Uni-CLI server if the local MCP HTTP transport was active. The Streamable HTTP transport already enforced proper browser-to-localhost boundaries, but the legacy stateless HTTP path did not, leading to this origin validation error. The vulnerability does not alter Uni-CLI's local code execution trust model. The issue was fixed in version 0.225.2.

An attacker controlling a malicious web page could send cross-origin POST requests to the local Uni-CLI server's MCP endpoint, potentially causing the server to execute commands on behalf of the user without proper origin validation. This could lead to unauthorized actions performed locally via the Uni-CLI interface. The vulnerability requires that the user has started the local MCP HTTP transport and interacts with the malicious page. There are no known exploits in the wild.

This vulnerability has been patched in Uni-CLI version 0.225.2. Users and administrators should upgrade to version 0.225.2 or later to ensure proper validation of browser Origin headers and prevent unauthorized command execution via the local MCP HTTP transport. No additional mitigation is required if the updated version is deployed.