Right, the ability for an attacker to change an XML file like this could be considered two separate issues. Things like this is why The Update Framework (TUF)

Right, the ability for an attacker to change an XML file like this could be considered two separate issues. Things like this is why The Update Framework (TUF) Specification was created: https://theupdateframework.github.io/ https://theupdateframework.github.io/ The specification covers exactly this kind of attack and has signing of all of the data about an update: https://github.com/theupdateframework/tuf/blob/develop/docs/tuf-spec.txt https://github.com/theupdateframework/tuf/blob/develop/docs/... But, as far as I know, there isn't an implementation of TUF that works with ObjectiveC and all the other parts of Sparkle, to actually update an OSX application.