If I recall correctly the issue was something like electrum permitted any full bitcoin node to broadcast any message and a nefarious node (since anybody can run

If I recall correctly the issue was something like electrum permitted any full bitcoin node to broadcast any message and a nefarious node (since anybody can run a node anonymously) broadcast a message to users to update their electrum client to a trojan client. Just goes to show that "security" is amatuerish in much of the bitcoin community. Bitcoin may be cryptographically secure but how people use it often is not. On top of all this around the same time I was trying to access some small amount of bitcoin in an older electrum wallet. It was no longer supported so I would have been forced to upgrade while there was this trojan variant going around. Any way what the lesson should be is when writing security critical software do it right the first time, don't force users to upgrade frequently, don't allow messages from anybody to be broadcast to users, don't break existing secure installations forcing users to upgrade unnecessarily. Keep it simple and secure. KISS.