I recently read an answer on this stackexchange that informed me that, if a person knows my IP, it can try to hack into my router and change the DNS in order to perform a MITM attack.
Now, this is coherent with what I have seen a few times: every day my router records 10-20 attacks that it blocks with its firewall.
However, I am mildly concerned about a thing: almost all operative systems, browsers, softwares I have been in contact with have very frequent security updates, said to be done "in order to fix vulnerabilities". I have never done, or be alerted that I should do, a router firmware update in my life. In particular, all my routers are 4+ years old.
Should I be concerned, or is there a specific reason for which a router doesn't need security updates? (either it performs them automatically, or there are no known vulnerabilities and it is a particularly safe system)