Slashdot Mirror
New WiFi Setup Flaw Allows Easy Router PIN Guessing
Trailrunner7 writes "There is a newly discovered vulnerability in the WiFi Protected Setup standard that reduces the number of attempts it would take an attacker to brute-force the PIN for a wireless router's setup process. The flaw results in too much information about the PIN being returned to an attacker and makes the PIN quite weak, affecting the security of millions of WiFi routers and access points. Security researcher Stefan Viehbock discovered the vulnerability (PDF) and reported it to US-CERT. The problem affects a number of vendors' products, including D-Link, Netgear, Linksys and Buffalo. 'I noticed a few really bad design decisions which enable an efficient brute force attack, thus effectively breaking the security of pretty much all WPS-enabled Wi-Fi routers. As all of the of the more recent router models come with WPS enabled by default, this affects millions of devices worldwide,' Viehbock said."
Don't you still have to physically push a button to (temporarily) enable WPS? If not, whose bright idea was *that*?
So I'm still safe-ish using plain old WPA2/PSK?
Since most people (home consumers) can't be bothered to change a default name/password/ssid on damn things anyway about 80% or more are unsecure as it it. If you want a secure connection, don't use the air, use a wire, and better yet, make sure you own and monitor its entire length.
Silence is a state of mime.
Same old thing, default configuration is bad.
"The flaw results in too much information about the PIN being returned to an attacker and makes the PIN quite weak"
Does anyone else visualize a router responding with: "Getting warmer!"
It sounds like all of your gear has been damned. That probably means that you have bigger things to worry about than security threats coming from this world.
Most of routers implementations allow a few attempts and then black list the MAC address of the attacker for a while (according to TFA the program would have to try at most 11,000 times).
Thus the attacker program should be low-level enough to fake its own MAC address all the time.
Slashdot, fix the reply notifications... You won't get away with it...
I use OpenWRT on my private router. As can be said of ALL default installed software: SCREW the firmware that comes with the routers.
It's just like my Laptop, Servers, Workstations, and Phone: If I can't install MY OS on it, it's not worth any of my time. If I haven't installed my OS on it, I DON'T USE IT.
That "easy setup" button on my router now gives me a minimal window of time during which I can SSH in to the router itself -- I have to be connected to the router already to do so over Ethernet or WPA2 w/ AES.
If you don't know how to drive GET THE HELL OUT from behind the steering wheel! The same can be said for networks, security, computers in general. If you can't configure your network, get someone who can to do so. Otherwise, expect to lose control and have a horrible accident when you brake instead of clutch, or WPS or WEP instead of WPA PSK w/ custom firmware.
After getting the "our developers are working on it" runaround for months and months when Linksys didn't issue new drivers without the Broadcom vulnerability for my WPC54G v.4 adapter, rendering it totally useless, I decided to never, never, buy Linksys equipment.
I actually "inherited" this card from a relative who had bought it and found out he didn't need it.
This really has to show you how bad Linksys's customer relations were with me: I didn't even pay for the adapter myself and Linksys still managed to totally piss me off with their lying stories about their developers working on new drivers.
(Disclaimer: I've posted this before here, when it was on-topic. I'll probably stop bothering to post it sometime in the next 10 years or so.)
From the PDF, the implementation mistake is to give the attacker feedback on whether the tried key is correct after the first half of authentication (phase M4), and then after the complete authentication (phase M6). Since the PIN is only 8 digits, and the last one is a checksum, the problem is reduced to guessing 1 number in 10000, and then 1 in 1000.
The document states that there are few possible mitigations for the problem. However, it skips the obvious one: do not notify authentication success/failure until the response to the M6 message. This would restore the 1 in 10,000,000 guessing complexity of the PIN code, without changing the protocol. It should even be a new issue tested by the compliance suite the vendors need to pass to get the WPS certification.
The attack in short: WPS NACKs a partially transmitted PIN if the first part is wrong. This leaves 20k trials needed for brute-force, instead of 1M.
I have no idea how people this incompetent get to design widely used protocols.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
If you don't use Tomato or DD-WRT on your router you obviously don't really care about security anyway so who cares? The OOB ROMs on most consumer routers are full of more holes than a breadboard.
BS. I can't speak to some brands, but the main reason to install Tomato or DD-WRT is *not* security, it's features. If you're not using one of those firmwares, then it's because you don't need the added features that they offer (or perhaps, you have a router which came with every single one of those features out of the box, and see no point in installing them). There is absolutely nothing that Tomato can do which can't be done with the default firmware on my TP-Link router, because the default firmware is that good. It literally does everything that Tomato does, and even provides a well-documented way to replace the firmware with Tomato if you still think it's better. (Tomato is mentionned specifically in the manual, as an example of why you'd use that feature in the firmware).
Tomato/DD-WRT are great for adding features like advanced QoS rules to an older router, or a router from a company that doesn't think that consumers need stuff like that, but they really don't improve the *security* at all. And that's largely because the *security* is all relying on the same protocols, and need to comply with standards like WPA2/PSK in order to play friendly with the computers you're trying to connect to it. If you're seriously worried about exploits to gain admin access to the firmware (assuming they even exist...), then you've already lost the battle, because it means that somebody you don't trust has already gotten access to your internal network.