Earlier quoted context omitted.
I think the theory is that once you have any beachhead onto a system, that existing local priv escalation exploits and network mapping techniques are almost always sufficient to complete the exploitation of your corporate network. So if you have 5 people using 5 different email clients, all 5 of those must be kept secure from spear phishing or email-viewing vulnerabilities to avoid having a hacker get a beachhead on…
> you only have to keep that 1 safe This argument may appeal to the self-indulgent system administrator who believes he alone knows perfection. In reality, there is no perfection. One must know there are things one does not know. If China is stock-piling zero days against Outlook, how are you to know? In fact, if there is anything we have learned from biological systems, surely it is that when a monoculture falls, it…
You're right that no one is perfect, but that's no reason to expand the number of directions threats can come from.