Irony: A networking spec designed to protect against TCP spoofing ended up making it easier. On the plus side, Linux is the only major OS that's implemented it so far. On the minus side…that's an awful lot of websites and Android phones.
Linux TCP flaw lets ‘anyone’ hijack Internet traffic
What started as an attempt to secure TCP/IP in Linux ended up enabling an attack vector that can be used to break, or even hijack, internet connections between Linux and Android systems.