There’s a common mistake that this is a problem for relativity but it is not. Relativity forbids is accelerating up to and past the speed of light but does not for bid particles that naturally travel faster than the speed of light. Such particles have been speculated about for decades under name tachyons.
The only real difficulty is that neutrinos have a small but real rest mass and so should not be traveling faster than the speed of light. In that case the issue is most likely with our understanding of neutrinos and relativity.
Quantum Mechanics allows particles to skip part of space instantly and so could be clocked at faster than the speed of light while going sub-light through the space it actually goes through. This is the most likely explanation of this observation given calculations from