CUB in Eze 30:5 is almost certainly a corruption of Lub (i.e. Lybia), as was read by Septuagint. The 'Libya' of AV is a mistranslation of Put (see RV). Cf. Na 3:9, where Lybians are mentioned along with Cush (Ethiopia), Egypt, and Put, as here; also 2Ch 12:3; 16:8.
with twelve hundred chariots and sixty thousand horsemen. And the people who came with him out of Egypt were without number: Lubim, the Sukkiim, and the Ethiopians.
Were not the Cushites and the Libyans a huge army with many chariots and horsemen? Yet, because you relied on Jehovah, he delivered them into your hand.
Ethiopia, and Libya, and Lydia, and all the mixed people; and Chub, and the men of the land who are in covenant with them shall fall by the sword.