Some 17 Netgear routers have a remote authentication bypass, meaning malware or miscreants on your network, or able to reach the device’s web-based configuration interface from the internet, can gain control without having to provide a password. Just stick &genie=1 in the URL, and bingo.

That’s pretty bad news for any vulnerable gateways with remote configuration access enabled, as anyone on the internet can exploit the cockup to take over the router, change its DNS settings, redirect browsers to malicious sites, and so on.

Another 17 Netgear routers – with some crossover with the above issue – have a similar bug, in that the genie_restoring.cgi script, provided by the box’s built-in web server, can be abused to extract files and passwords from its filesystem in flash storage – it can even be used to pull files from USB sticks plugged into the router.

Other models have less severe problems that still need patching just in case. For example, after pressing the Wi-Fi Protected Setup button, six of Netgear’s routers open up a two-minute window during which an attacker can potentially execute arbitrary code on the router as root over the air.

Source: Wish you could log into someone’s Netgear box without a password? Summon a &genie=1 • The Register