Safe network please

This is very important information and it tells a tale about the need to keep maintaining bitcoin's code so that the network can stay safe.

A big thank you to all contributors that help the bitcoin network stay secure.

Thanks to everyone who selflessly devote their time on enhancing Bitcoin's security.

the core 0.21.0 could allow a remote attacker to cause a denial of service (DoS) by sending a specially crafted addr message to the node, causing it to crash