hashcat does not use the processor to its full capacity

[penguinkeeper]

As the forum has hilariously pointed out, that distro is really not very good with OpenCL and can cause a lot of issues, especially if it's being virtualised, which brings in significant blockers for performance. Running it on your host machine and in another distro or Windows will likely fix your issue. Also, GPUs are often leagues better, even a low-end GPU will often beat a high-end CPU in hashing performance, so if it's possible to switch to a GPU, that'd be ideal