Mem0 versions through 0.2.8, fixed in commit ae7f406, contain a missing authorization vulnerability in the self-hosted server component where the POST /configure endpoint modifies global LLM provider and embedder configuration but only verifies authentication via JWT or X-API-Key without validating the caller's role. Any authenticated user holding a distributed API key can redirect all LLM and embedder traffic to an attacker-controlled server, with the malicious configuration persisted to PostgreSQL and surviving server restarts to affect all users and API keys on the instance.