Ubisoft Confirms Rainbow Six Siege Server Breach Linked to MongoBleed Vulnerability

Ubisoft experienced a critical breach via the MongoBleed vulnerability (CVE-2025-14847) allowing unauthenticated, network-based arbitrary data reads and memory disclosure; attackers tampered with millions of Rainbow Six Siege accounts (mass in-game currency fraud and unlocked cosmetics), weaponized the anti-cheat ban system for messaging, and reportedly exfiltrated ~900GB of sensitive materials including source code and SDKs. Ubisoft confirmed the incident, took servers offline for maintenance, plans a data rollback, and advised players to avoid Ubisoft Connect until integrity is verified.