There seems to be some asymmetry in prototype pollution between functions and “plain”¹ objects:

var a = {}
function foo(){}

a.__proto__.something = 32;
foo.__proto__.bar = 67;

console.log(a.bar) // <--- not polluted
console.log(foo.something) // <--- polluted

• The example shows that plain objects can pollute functions
• Is the other way around possible too? (functions polluting plain objects)

¹ terminology is not a consensus (see here)