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+# Critical Issue Resolution: security: Add CORS validation checks on socket handshake connection requests
+
+## Overview
+Introduce strict origin checks during connection initialization to protect sockets from cross-site WebSocket hijacking (CSWSH) attempts.
+
+## Implementation Checklist
+- [x] Write architectural documentation
+- [x] Create components in `backend/config/socket_cors.py`
+- [x] Run verification criteria checks
+
+Closes #559
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