On August 1, 2022, Nomad bridge was exploited when the protocol initialization set trusted roots to 0x00, matching the untrusted root value. This caused the Replica contract to accept any messages as valid, enabling 300+ copycat attackers to drain $190M total.

The Nomad Bridge, a cross-chain interoperability protocol, was attacked by hackers. This attack was due to the fact that the trusted root of the Nomad Bridge Replica contract was set to 0x0 during initialization, and the old root was not invalidated when the trusted root was modified. Constructing arbitrary messages to steal funds from the bridge, the attacker was able to extract over $190 million in value from the attack. So far, more than 40 addresses have returned over $36 million to Nomad.