Many of the best-selling consumer and SOHO wireless routers are wide open to attackers thanks to known software vulnerabilities and poor configuration, a study by security firm Tripwire has found.

Worries about the parlous state of home router security are far from new, but Tripwire’s probing is a good reminder of the vulnerability of this class of devices.

Using the top 50 selling home routers for sale on Amazon, the firm detected software vulnerabilities in three quarters with a third of these having publically documented flaws open for any attacker to exploit. Common problems included vulnerable management interfaces and dodgy authentication.

Disturbingly, there was also evidence of identical flaws across products from different vendors indicating the possibiliity of a common but undocumented software heritage.

After surveying router users in person, the firm found that many user don’t change the default admin password (an ancient problem), few had changed the default 192.168.1.x IP address (which facilitates CSRF attacks), and almost nobody bothered to update firmware assuming an update was even available.

There’s no argument that home routers are a security blindspot, but are these fears being a bit overblown?

While attacking a home router would offer the ability to control, direct and in some cases eavesdrop on traffic, it’s not immediately obvious that criminals would be able to carry off widespread attacks.

The biggest problem for an attacker is simply that home routers are fragmented across a range of vendors and product generations; getting traction against these devices would be no mean feat when there are far easier targets such as the ubiquitous Windows computer to shoot down instead.

The obvious exception to this are the mass-market routers now handed out in the UK and other countries by large ISPs. If criminals wanted to target routers it would likely be against everyone within a given country using a particular provider's product.

Although to date no major attacks hijacked home routers on an industrial scale, recently the warning lights have started flashing red.

Only days ago, the Moon worm targeting Linksys routers gained some publicity while last month UK broadband network EE had to issue a security fix after a flaw was found in its Brightbox broadband routers. Poland’s CERT issued a warning about attacks on home routers in in the country as part of an attempt to finesse DNS settings in online bank attacks.

Going back a year, Rapid7 issued a more general warning over the vulnerability of the UPnP protocol which is enabled on many routers by default.

The biggest worry of all is that an attack on a home router might not be discovered for a considerable period of time, or even at all. These attacks could yet be the perfect cybercrimes.

“Unfortunately, users don’t change the default administrator passwords or the default IPs in these devices and this behaviour, along with the prevalence of authentication bypass vulnerabilities, opens the door for widespread attacks through malicious web sites, browser plugins, and smartphone applications,” said Tripwire researcher, Craig Young.