metadata.js

const cbor = require('cbor')

const bytecode = '70656e6420696e707574206e6f7465415a54454320617272617920696e646578206973206f7574206f6620626f756e6473a265627a7a7231582011639b922cf661bed862dc70ef7a0a62211ae58261383916450efb20b2fd6a4164736f6c63430005100032'

// last two bytes are 0032, interpreted in hex is 50, so length in hex is 100
// the metadata bytes are the last 100 chars, excluding the last 4 which are the size
const metadata = bytecode.slice(bytecode.length - 104, bytecode.length - 4)

const { solc } = cbor.decode(metadata)

console.log(solc.toString('hex'));

// this logs 000510, which means solc 0.5.16 was used