The vast majority of punters are potentially leaving themselves exposed to miscreants by failing to change the password and security setting on their routers - according to a survey.
Some 82 per cent said they had never changed their administrator password, a poll of 2,205 people by Brit comparison website Broadband Genie found. And 52 per cent also admitted to never having changed the network name, updated firmware, or checked to see what devices are on their network.
When quizzed further, 48 per cent said they were baffled as to why they would need to make those changes, while 34 per cent said they didn't know how.
Broadband Genie claimed the findings suggested that as well as patching security holes and upgrading hardware, ISPs should also be ensuring they offer help pitched at complete beginners, including explanations of why it is important to secure Wi-Fi routers.
Pen Test Partners' Ken Munro said ISPs have known about this issue for years. "They're only now doing stuff following the TalkTalk breach. But they definitely could have done more. Frankly, I'm surprised there aren't more incidents."
He noted that with the onset of connected devices in the home, it is possible to hack a variety of devices after obtaining the Wi-Fi key, including changing the thermostats and lighting, or getting the smart TV to control the home's audio.
"The problem is Wi-Fi router passwords are really there to get people started, they come with default keys, with the numbers and letters usually in the same place, that can take literally seconds to crack.
"ISPs have been improving, but the point is there is a huge install base of routers with really weak keys."
Andy Patel, security expert at F-secure, agreed that newer routers tend to come with a randomised Wi-Fi Protected Access passwords.
"Those aren't going to be guessable by attackers. However, I'm not sure that the admin interface for the router would have been set up with a similarly randomised password.
"Hence, if an attacker can access that admin interface, he/she could probably log in by guessing the default password and then change settings, including the Wi-Fi password itself. There are other nasty things you can do if you can get access to this interface.
"Some malware actually implements features that, after infecting a computer, look for router admin interfaces on the local network, try to guess the admin login credentials, and then install IoT botnets on those devices."
He added that this sort of attack could be used for routers that are serving public Wi-Fi hotspots.
"If you change the Domain Name Service settings in that router, you can redirect all users to poisoned DNS servers that can contain bogus IP addresses for common web services." ®