CertGraph

Certgraph is a tool I’ve been developing to scan and graph the network of SSL certificate alternative names. It can be used to find other domains that belong to an organization that may be several orders removed and not always obvious. Background The idea for this project came about after examining the SSL certificate for XKCD.com. If you look closely at the screenshot below you will see that the SSL certificate used on XKCD.com is also valid for many of domains which have no relationship to XKCD or Randall Munroe. ...

April 6, 2018 · 7 min · Ian Foster

Tethr: Android Tethering Provisioning Check Bypass (CVE-2017-0554)

On most unrooted, stock, Android phones, enabling tethering will run a “Provisioning Check” with your wireless provider to ensure that your data plan allows tethering. This post documents Tethr, a way to bypass the provisioning check on Android devices prior to version 7.1.2. After discovering this method I reported it to the Android bug bounty fixing the issue and receiving CVE-2017-0554. Background The ability to tether is controlled by your device’s build.prop file, usually located at /system/build.prop. The default is to require the provisioning check before enabling tethering, but it can by bypassed by adding the following line: ...

December 27, 2017 · 4 min · Ian Foster

Ambergris

For those of you not in the know, ambergris is defined as: a wax-like substance that originates as a secretion in the intestines of the sperm whale, found floating in tropical seas and used in perfume manufacture. However, that will not be what this post is about (sorry to disappoint). Instead, I’ll present what happens when building an image on Docker that contains a reverse shell in the Dockerfile. ...

January 19, 2017 · 7 min · Ian Foster

Badgy

A while ago I came into possession of a few HID iClass readers. After collecting dust in my project drawer for a few months I decided to find a fun use for them, which ended up in the project I call Badgy. Background The back of the HID readers have 10 colored wires coming out of them. Luckily the readers also had a nice sticker telling me which wire was what. ...

December 24, 2016 · 7 min · Ian Foster

Solving the Challenge of Tiamat's Eye

Last week at DerbyCon 5.0 the CircleCityCon folks had a booth with a challenge, the Challenge of Tiamat’s Eye. @CircleCityCon: Can you solve the Puzzle of Tiamat's Eye? Visit our booth at @DerbyCon to take the challenge! pic.twitter.com/yJzPvxOQk9 — CircleCityCon 10.0: WHODUNIT? (@CircleCityCon) September 26, 2015 The challenge consisted of the small chest pictured above containing an eye made up of blinking red LEDs. Every 30 seconds the pattern would reset. The content organizers hinted that we would need to record the eye at 60fps in order to capture all of the information we needed. We ended up using a coffee creamer cup as a diffuser over the LEDs to make the difference in the pixels clearer. This resulted in the following recording. Note: we recorded 30 seconds at 60fps, which resulted in a 60 second 30fps recording. ...

October 3, 2015 · 3 min · Ian Foster

Sonic IPv6 Tunnel with DD-WRT

Sonic (my home ISP) offers an IPv6 tunnel for their customers who have a service plan that does not offer native IPv6 yet. Sonic’s IPv6 tunnel operates much the same way Hurricane Electric’s Tunnel Broker does, however since the endpoint is located inside the ISP you should get better performance. Sonic even offers example configurations for configuring the IPv6 tunnel endpoint on various operating systems, but none for DD-WRT, a common aftermarket router firmware. Another Sonic user did document how to configure Sonic’s IPv6 tunnel with older versions of DD-WRT on the Sonic forums at dev-random.me, however the link appears to be dead. Additionally newer versions of DD-WRT have a new IPv6 tab which should allow for a painless configuration using nothing more than the web interface. ...

August 17, 2015 · 5 min · Ian Foster

Fast and Vulnerable: A Story of Telematic Failures

I gave a presentation at WOOT 2015 demonstrating how network enabled telematic control units (TCUs) can be used to remotely control automobiles from arbitrary distance over SMS or the Internet. Abstract Modern automobiles are complex distributed systems in which virtually all functionality, from acceleration and braking to lighting and HVAC, is mediated by computerized controllers. The interconnected nature of these systems raises obvious security concerns and prior work has demonstrated that a vulnerability in any single component may provide the means to compromise the system as a whole. Thus, the addition of new components, and especially new components with external networking capability, creates risks that must be carefully considered. ...

August 11, 2015 · 2 min · Ian Foster

PSA: Enable server certificate revocation checking in Chrome

Recently there has been a lot of buzz about the recent Heartbleed vulnerability found in some versions of OpenSSL. The attack works due to a mistake in the server validating part of the request made by the SSL client. The popular web comic XKCD has made a great simple comic explaining how the attack works, and there are simple tools to test for vulnerable servers. But how does this affect me, a user? ...

April 14, 2014 · 2 min · Ian Foster

TRIPLEX DVRLink DVR468RW Exploit

At an internship I had a while ago one project assigned to me was to regain access to a CCTV security system which we had been locked out of for some years. (The previous manager left without leaving the password.) The DVR system was a TRIPLEX DVRLink DVR468RW, whatever that is. It seemed cheap; a small embedded computer with video in/out, a hard-drive and CD-RW drive for recording storage. The administration interface was accessed either by a web server running on the device or a desktop client you installed on your computer. ...

June 20, 2013 · 3 min · Ian Foster

Getting Started with ActionBarSherlock

Update ActionBarSherlock is no longer necessary. The latest Google Support Library includes appcompat which is a better solution. ...

June 11, 2013 · 3 min · Ian Foster

How to Compile a Linux Kernel for Android

A while ago I was working on building a custom kernel for my Android phone. Once you get the source the compilation process is not as straightforward as I hoped. Here are the steps required to get from the kernel source to a flashable image for your phone. Get a copy of the build toolchain and Linux kernel for your device First download a copy of the pre-build toolchain from git. ...

May 27, 2013 · 3 min · Ian Foster

Adding Hibernate to the CrunchBang Linux shutdown menu

By default CrunchBang Linux does not have hibernation support enabled in the shutdown menu. The reason for being excluded is likely because not all computers support hibernation. However most modern computers will support it. To add a hibernation option just download this file and place it in the bin directory of your home folder: “~/bin/” and make it executable with: chmod +x cb-exit cb-exit Gist If you want to test your system to see if it can handle hibernation run the following command. If your system supports it you should be able to successfully enter and exit hibernation: ...

May 25, 2013 · 1 min · Ian Foster

PHP Karaoke Queue

A while ago I decided that I needed some more JavaScript/AJAX experience, and what better way to get it than to use it to solve an existing problem. Every now and then my apartment hosts karaoke nights, we have a lot of songs, enough to fill a 4-inch binder. Searching for songs was a pain. In order to find the song’s ID code to give to the DJ you must search through pages of songs and artists that were in no particular order. I decided to fix this problem with my skill set, so I created DJQueue. DJQueue is a collection of hacked together PHP, JavaScript, and SQL magic. ...

May 25, 2013 · 1 min · Ian Foster

SMS DOS: Cellphone Denial Of Service via text messages

A while ago I wondered how well modern cellphones could handle a flood of text messages. So I created a simple python program to test just that. The program works by sending emails to a SMS Gateway which will forward the message to the phone in the form of a text message. I tested my program on two devices, my modern HTC Incredible running Android and my aging LG Chocolate dumb-phone. The results where surprising! After starting the program my HTC Incredible froze after receiving the first 20 messages. A battery pull was required to get it to respond. The second it finished booting it froze again! I was only able to make it respond by stopping my program and rebooting the phone. After it boot it froze again while catching up on all the messages that where sent. ...

March 11, 2012 · 2 min · Ian Foster

WIFI Recovery for Android

Have you ever wanted to give a friend access to a wireless network you are on but don’t want to go find the key? WIFI Key Recovery will find the key on your device and allow you to share it via a message or QR Code. Additionally WIFI Key Recovery will allow you to backup/restore your current WIFI configuration to your SD card! If this app does not work on your rooted phone email me I will try to add support. ...

March 1, 2012 · 1 min · Ian Foster