Is Rust legal in Standard, Modern, and Commander?

Rust is legal in: Legacy, Vintage, Commander, Pauper.

Rust

Rust is an Instant. Its oracle text reads: "Counter target activated ability from an artifact source. (Mana abilities can't be targeted.)"

Instant

Counter target activated ability from an artifact source. (Mana abilities can't be targeted.)

Set Legends

Rarity Common

Artist Liz Danforth

Instant Counterspell Commander Pauper Legacy