Security is always first for THORChain, and recently, THORChain Node operators practiced a drill called "Code Red".
Because nodes have the most at stake and globally monitor the network 24/7, the Code Red feature makes it possible for a node to pause the network for 1hr if they spot anything suspicious. Any other node can unpause.
If the network (or a bifrost) is ever compromised then it can quickly pause signing. The txOut queue will grow, but the network can react. A node can only pause once per 7 days and any node can unpause as soon as possible.
This feature helps keep the network/funds safe and minimize a potential exploit.
Other security features available are: