The Crypt::decript function stopped working after the Laravel 4.2 to 5.0 update

After the update of L4.2 to L5 the function Crypt::decrypt doesn't work for the hashes generated on L4.2, however my APP_KEY still the same.

DecryptException in Encrypter.php line 147:
MAC is invalid.

My hashes generated after the update does work, but not for the ones before the migration;

via Chebli Mohamed