Hack into some database to steal bioweapon designs (or invent one by itself), get a few chemical companies to assemple components, bribe some poor schmuck into mixing the vials together, boom.
THB though, what I fear is individuals. Humans as a group behave often in batshit insane ways, but most of the time, they're a peaceful and kind species. But you always have, by the random lottery of genes and environment, crazy people. What technology does is magnifying the power a single person can wield, and thus the damage they can do. Self-replicating stuff is particularly nasty power amplifier here.
Hack into some database to steal bioweapon designs (or invent one by itself), get a few chemical companies to assemple components, bribe some poor schmuck into mixing the vials together, boom.
THB though, what I fear is individuals. Humans as a group behave often in batshit insane ways, but most of the time, they're a peaceful and kind species. But you always have, by the random lottery of genes and environment, crazy people. What technology does is magnifying the power a single person can wield, and thus the damage they can do. Self-replicating stuff is particularly nasty power amplifier here.