ncat

What sources do you have in /etc/apt/sources.list and /etc/apt/sources.list.d/ ?

ncat used to be part of nmap up until a few months ago:

nmap (7.70+dfsg1-2) unstable; urgency=medium

[...]

• Ship ncat as separate package, provide nc alternative
  (Closes: #881639, #560377)

  -- Hilko Bengen <[email protected]> Sun, 08 Apr 2018 22:17:31 +0200

If you still have an old nmap available in one of your configured repositories, then this inaccuracy is to be expected

Thank you, this are my repos:

deb https://http.kali.org/kali kali-rolling main non-free contrib
deb-src https://http.kali.org/kali kali-rolling main non-free contrib
deb http://old.kali.org/kali sana main non-free contrib
deb-src http://old.kali.org/kali sana main non-free contrib

Maybe the problem are the "old" ones?

Yes, please remove those old sana entries and this won't happen anymore.