Having implemented CBOR [1], it's really only an issue for the x86, which can do unaligned reads. On most other architectures (even little-endian ones like RISC-V) it's less an issue because you will either have to copy the bytes to be aligned, or just read byte-by-byte (sorry, octet-by-octet) and shift.

[1] https://github.com/spc476/CBOR