Yik Yak MITM Hack (Give The Dog A Bone)

December 10, 2014 by Rick Osgood 24 Comments

Yik Yak is growing in popularity lately. If you are unfamiliar with Yik Yak, here’s the run down. It’s kind of like Twitter, but your messages are only shared with people who are currently within a few miles of you. Also, your account is supposed to be totally anonymous. When you combine anonymity and location, you get some interesting results. The app seems to be most popular in schools. The anonymity allows users to post their honest thoughts without fear of scrutiny.

[Sanford Moskowitz] decided to do some digging into Yik Yak’s authentication system. He wanted to see just how secure this “anonymous” app really is. As it turns out, not as much as one would hope. The primary vulnerability is that Yik Yak authenticates users based solely on a user ID. There are no passwords. If you know the user’s ID number, it’s game over.

The first thing [Sanford] looked for was an encrypted connection to try to sniff out User ID’s. It turned out that Yik Yak does actually encrypt the connection to its own servers, at least for the iPhone app. Not to worry, mobile apps always connect to other services for things like ad networks, user tracking, etc. Yik Yak happens to make a call to an analytics tool called Flurry every time the app is fired. Flurry needs a way to track the users for Yik Yak, so of course the Yik Yak App tells Flurry the user’s ID. What other information would the anonymous app have to send?

Unfortunately, Flurry disables HTTPS by default, so this initial communication is in plain text. That means that even though Yik Yak’s own communications are protected, the User ID is still exposed and vulnerable. [Sanford] has published a shell script to make it easy to sniff out these user ID’s if you are on the same network as the user.

Once you have the user ID, you can take complete control over the account. [Sanford] has also published scripts to make this part simple. The scripts will allow you to print out every single message a user has posted. He also describes a method to alter the Yik Yak installation on a rooted iPhone so that the app runs under the victim’s user ID. This gives you full access as if you owned the account yourself.

Oh, there’s another problem too. The Android app is programmed to ignore bad SSL certificates. This means that any script kiddie can perform a simple man in the middle attack with a fake SSL certificate and the app will still function. It doesn’t even throw a warning to the user. This just allows for another method to steal a user ID.

So now you have control over some poor user’s account but at least they are still anonymous, right? That depends. The Yik Yak app itself appears to keep anonymity, but by analyzing the traffic coming from the client IP address can make it trivial to identify a person. First of all, [Sanford] mentions that a host name can be a dead giveaway. A host named “Joe’s iPhone” might be a pretty big clue. Other than that, looking out for user names and information from other unencrypted sites is easy enough, and that would likely give you everything you need to identify someone. Keep this in mind the next time you post something “anonymously” to the Internet.

[via Reddit]

The Last Week Of The Mooltipass Approacheth

December 8, 2014 by Brian Benchoff 46 Comments

A year and two days ago, [Mathieu] started out on a quest to develop some hardware with the help of Hackaday readers. This project became known as the Mooltipass, an open source offline password keeper that’s pretty much a password management suite or Post-It notes on a monitor, except not horribly insecure.

The product has gone through multiple iterations of software, [Mathieu] flew out to China to get production started, and the project finally made it to a crowdfunding site. That crowdfunding campaign is almost over with just eight days left and just a little bit left to tip this project into production. This is the last call, all hands in, and if you’re thinking about getting one of these little secure password-storing boxes, this is the time.

You can check out the Developed on Hackaday series going over the entire development of the Mooltipass, made with input from Mooltipass contributors and Hackaday readers. The Venn diagram of those two groups overlaps a lot, making this the first piece of hardware that was developed for and by Hackaday readers.

Even if you have a fool-proof system of remembering all your passwords and login credentials, the Mooltipass is still a very cool-looking Arduino-compatible board. Note that (security device) and (Arduino thing) are two distinct operating modes that should not be conflated.

[Mathieu] and other contributors will be in the comments below, along with a bunch of ‘security researchers’ saying how this device ‘is horrifying’, ‘full of holes’, and ‘a terrible idea’. One of these sets of people have actually done research. Guess which?

Bad Code Results In Useless Passwords

December 7, 2014 by Rick Osgood 18 Comments

[HeadlessZeke] was excited to try out his new AT&T wireless cable box, but was quickly dismayed by the required wireless access point that came bundled with it. Apparently in order to use the cable box, you also need to have this access point enabled. Not one to blindly put unknown devices on his network, [HeadlessZeke] did some investigating.

The wireless access point was an Arris VAP2500. At first glance, things seemed pretty good. It used WPA2 encryption with a long and seemingly random key. Some more digging revealed a host of security problems, however.

It didn’t take long for [HeadlessZeke] to find the web administration portal. Of course, it required authentication and he didn’t know the credentials. [HeadlessZeke] tried connecting to as many pages as he could, but they all required user authentication. All but one. There existed a plain text file in the root of the web server called “admin.conf”. It contained a list of usernames and hashed passwords. That was strike one for this device.

[HeadlessZeke] could have attempted to crack the passwords but he decided to go further down this rabbit hole instead. He pulled the source code out of the firmware and looked at the authentication mechanism. The system checks the username and password and then sets a cookie to let the system know the user is authenticated. It sounds fine, but upon further inspection it turned out that the data in the cookie was simply an MD5 hash of the username. This may not sound bad, but it means that all you have to do to authenticate is manually create your own cookie with the MD5 hash of any user you want to use. The system will see that cookie and assume you’ve authenticated. You don’t even have to have the password! Strike two.

Now that [HeadlessZeke] was logged into the administration site, he was able to gain access to more functions. One page actually allows the user to select a command from a drop down box and then apply a text argument to go with that command. The command is then run in the device’s shell. It turned out the text arguments were not sanitized at all. This meant that [HeadlessZeke] could append extra commands to the initial command and run any shell command he wanted. That’s strike three. Three strikes and you’re out!

[HeadlessZeke] reported these vulnerabilities to Arris and they have now been patched in the latest firmware version. Something tells us there are likely many more vulnerabilities in this device, though.

[via Reddit]

SpoofedMe Attack Steals Accounts By Exploiting Social Login Mechanisms

December 5, 2014 by Rick Osgood 34 Comments

We’ve all seen the social logon pop up boxes. You try to log into some website only to be presented with that pop up box that says, “Log in with Facebook/Twitter/Google”. It’s a nice idea in theory. You can log into many websites by using just one credential. It sounds convenient, but IBM X-Force researchers have recently shown how this can be bad for the security of your accounts. And what’s worse is you are more vulnerable if the service is offered and you are NOT using it. The researcher’s have called their new exploit SpoofedMe. It’s aptly named, considering it allows an attacker to spoof a user of a vulnerable website and log in under that user’s account.

So how does it work? The exploit relies on vulnerabilities in both the identity provider (Facebook/Twitter/etc) and the “relying website”. The relying website is whatever website the user is trying to log into using their social media account. The easiest way to describe the vulnerability is to walk through an example. Here we go.

Let’s imagine you are an attacker and you want to get into some victim’s Slashdot account. Slashdot allows you to create a local account within their system if you like, or you can log in using your LinkedIn account. Your victim doesn’t actually have a LinkedIn account, they use a local Slashdot account.

The first step of your attack would be to create a LinkedIn account using your victim’s email address. This needs to be the same address the victim is using for their local Slashdot account. This is where the first vulnerability comes in. LinkedIn needs to allow the creation of the account without verifying that the email address belongs to you.

The second step of the attack is now to attempt to log into Slashdot using your newly created LinkedIn account. This is where the second vulnerability comes in. Some social media services will authenticate you to websites like Slashdot by sending Slashdot your user information. In this case, the key piece of information is your email address. Here’s the third vulnerability. Slashdot sees that your LinkedIn account has the same email address as one of their local users. Slashdot assumes that LinkedIn has verified the account and permits you, the attacker, to log in as that user. You now have access to your victim’s Slashdot account. In another scenario, Slashdot might actually merge the two credentials together into one account.

What’s really interesting about this hack is that it isn’t even very technical. Anyone can do this. All you need is the victim’s email address and you can try this on various social media sites to see if it works. It’s even more interesting that you are actually more vulnerable if you are not using the social logons. Some real world examples of this vulnerability are with LinkedIn’s social logon service, Amazon’s service, and MYDIGIPASS.com’s service. Check out the demonstration video below. Continue reading “SpoofedMe Attack Steals Accounts By Exploiting Social Login Mechanisms” →

Hiding Executable Javascript In Images That Pass Validation

November 15, 2014 by Mike Szczys 18 Comments

Here’s an interesting proof-of-concept that could be useful or hazardous depending on the situation in which you encounter it. [jklmnn] drew inspiration from the work of [Ange Albertini] who has documented a way to hide Javascript within the header of a .gif file. Not only does it carry the complete code but both image and the Javascript are seen as valid.

With just a little bit of work [jklmnn] boiled down the concept to the most basic parts so that it is easy to understand. Next, a quick program was written to automate the embedding of the Javascript. Grab the source code if you want to give it a try yourself.

Let’s get back to how this might be useful rather than harmful. What if you are working on a computer that doesn’t allow the browser to load Javascript. You may be able to embed something useful, kind of like the hack that allowed movies to be played by abusing Microsoft Excel.

Reverse Engineering The D-Link WPS Pin Algorithm

October 31, 2014 by Brian Benchoff 36 Comments

A router with WPS requires a PIN to allow other devices to connect, and this PIN should be unique to every router and not derived from other easily accessible data found on the router. When [Craig] took a look at the firmware of a D-Link DIR-810L 802.11ac router, he found exactly the opposite; the WPS PIN was easily decipherable because it was generated entirely from the router’s MAC address and could be reverse engineered by sniffing WiFi.

When [Craig] was taking a look at the disassembled firmware from his router, he noticed a bit of code that accessed the NVRAM used for storing device-specific information like a serial number. This bit of code wasn’t retrieving a WPS pin, but the WAN MAC address instead. Instead of being unique to each device and opaque to every other bit of data on the router, the WPS pin was simply generated (with a bit of math) from the MAC address. This means anyone upstream of the router can easily derive the WPS pin of the router, and essentially gives everyone the keys to the castle of this router.

A few years ago, it was discovered the WPS pin was extremely insecure anyway, able to be brute-forced in a matter of minutes. There are patches router manufacturers could apply to detect these brute force attacks, closing that vulnerability. [Craig]’s code, though, demonstrates that a very large number of D-Link routers effectively broadcast their WPS PIN to the world. To make things even worse, the BSSID found in every wireless frame is also derived from the WAN MAC address. [Craig] has literally broken WPS on a huge number of D-Link routers, thanks to a single engineer that decided to generate the WPS PIN from the MAC address.

[Craig] has an incomplete list of routers that are confirmed affected on his site, along with a list of confirmed unaffected routers.

A Better Anonabox With The Beaglebone Black

October 31, 2014 by Brian Benchoff 29 Comments

A few weeks ago, Anonabox, the ill-conceived router with custom firmware that would protect you from ‘hackers’ and ‘legitimate governments’ drew the ire of tech media. It was discovered that this was simply an off-the-shelf router with an installation of OpenWrt, and the single common thread in the controversy was that, ‘anyone can build that. This guy isn’t doing anything new.’

Finally, someone who didn’t have the terrible idea of grabbing another off the shelf router and putting it up on Kickstarter is doing just that. [Adam] didn’t like the shortcomings of the Anonabox and looked at the best practices of staying anonymous online. He created a Tor dongle in response to this with a Beaglebone Black.

Instead of using wireless like the Anonabox and dozens of other projects, [Andy] is using the Beaglebone as a dongle/Ethernet adapter with all data passed to the computer through the USB port. No, it doesn’t protect your entire network; only a single device and only when it’s plugged in.

The installation process is as simple as installing all the relevent software, uninstalling all the cruft, and configuring a browser. [Adam] was able to get 7Mb/sec down and 250kb/sec up through his Tor-ified Ethernet adapter while only using 40% of the BBB’s CPU.