arstechnica[.]com/information-technology/2020/01/exploit-that-gives-remote-access-affects-200-million-cable-modems/
Cable Haunt, as the researchers have named their proof-of-concept exploit, is known to work on various firmware versions of the following cable modems:Sagemcom F@st 3890
Sagemcom F@st 3686
Technicolor TC7230
Netgear C6250EMR
Netgear CG3700EMRThe exploit may also work against the Compal 7284E and Compal 7486E. Because the spectrum analyzer server is present in other cable modems, the exploit is likely to work on other models as well.
If an attacker were to gain control of your modem they have access to all traffic in & out, and can control what happens when you try to connect online, e.g. if you enter giveawayoftheday on the address bar of your browser, they can have it open a fake GOTD site that offers malware [ransomware etc.] instead of the legitimate downloads. If you use the F/Book login they might capture your credentials as well, gaining control of that account.