CVE-2026-85695: FastChat authentication bypass in the /register_worker endpoint

Summary

FastChat contains an authentication bypass in the /register_worker endpoint that lets unauthenticated attackers register arbitrary worker addresses and perform server-side request forgery. Attackers can register malicious workers under victim model names to intercept user prompts, images, and responses, or probe internal network ports across the worker mesh.

Mitigation

The source does not state a fix yet. Check the original advisory for updates.

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