Schedule

Schedule

Friday, December 19

1419033600 Tech News 2Night

Saturday, December 20

1419102000 The Tech Guy

Sunday, December 21

1419188400 The Tech Guy
1419202800 This Week in Tech

Monday, December 22

1419271200 Tech News Today
1419274800 Triangulation
1419280200 iPad Today
1419292800 Tech News 2Night

Tuesday, December 23

1419357600 Tech News Today
1419361200 MacBreak Weekly
1419368400 Security Now
1419375600 Before You Buy
1419379200 Tech News 2Night
1419382800 All About Android
1419391800 Padre's Corner

Wednesday, December 24

1419444000 Tech News Today
1419447600 Windows Weekly
1419454800 This Week in Google
1419465600 Tech News 2Night

Thursday, December 25

1419530400 Tech News Today
1419534000 Know How...
1419537600 Marketing Mavericks
1419543000 Coding 101
1419546600 Home Theater Geeks
1419553800 The Giz Wiz

Friday, December 26

1419616800 Tech News Today
1419638400 Tech News 2Night

Saturday, December 27

1419706800 The Tech Guy

Sunday, December 28

1419793200 The Tech Guy
1419807600 This Week in Tech

Monday, December 29

1419876000 Tech News Today
1419879600 Triangulation
1419885000 iPad Today

Most Recent Episodes

Tech News Today

The BBC has aired a new documentary slamming Apple

This Week in Computer Hardware

AMD Omega Driver, mechanical keys, and Broadwell NUC pics.

The Giz Wiz
Episode #1498: Inflate My Ego December 18th, 2014

TalkBand, disco lights, inflatable chair, and more!

Home Theater Geeks

Multichannel audio, speaker placement, and multiple subwoofers.

Tech News 2Night

A Security Flaw in Millions of Routers

Coding 101

Polishing up the holiday pricer.

Marketing Mavericks
Episode #35: Game of Drones December 18th, 2014

Taking an idea and taking off with it

Know How...

In case you didn't know this is Episode 123

Tech News Today

Hollywood caves in the face of threats from the Sony hackers.

Ham Nation

Ham Emergency Radio Operations(H.E.R.O) lends aid in the recent Philippine typhoon.

Know How... 106

Bad USB, I Am Groot, and Defcon

August 14 2014

A USB hack that will make you drop your packets, Patrick Djelahanty shows how he built the "Baby Groot" out of common parts, see soundwaves, lock picking, and Defcon wrap up.

"Bad USB"
* German Researchers Karsten Knoll and Jacob Lell discovered an exploit in the way USB works
* ALL USB devices use some form of controller. They're small computers that interface the USB serial communications protocol with whatever device we want to connect via USB.
-- That controller is actually a small computer... and the computer runs an operating system that is determined by firmware.

What's the Exploit?
* The way that USB was created, that firmware is updateable. It's updateable because the creators of the USB standard wanted manufacturers to be able to reprogram the firmware if a flaw was ever discovered in that firmware.
* HOWEVER, that also means that a malicious user (hacker) could reprogram the firmware to make the device act in a way that the manufacturers had not intended.

What does that all mean?
* This means that a USB flash drive could be reprogramed to act like a keyboard
-- So after you plug it in, it issues a series of keystrokes that (for example) open Internet Explorer, navigate to a page that contains malware, then close the browser... all in a matter of seconds
* Or a USB flash drive could be reprogrammed to act like a network adapter
-- All the traffic you send and receive from your network would pass through this new network adapter, which would forward the packet stream to another computer before sending your trafic to the proper destinations.

Worse still... since your computer has USB devices INTEGRATED into the system (Keyboard, Mouse, Webcamera, Card Reader) a compromised USB device could be used to compromise the USB devices in your computer, which would then compromise any USB device that connects to your computer.

Ok... so why not just run an anti-virus? Or copy over new firmware? Or just make USB firmware non-programmable?

Let's take that one at a time: Anti-Virus
* Your system cannot see past the controller of a USB device.
-- The way USB devices work, the system can query the controller, and the controller will tell the system the status of the USB device.
-- If the controller is compromised, then you cannot trust it to report the correct status
** In other words, the only way an Anti-Virus would work would be if the malware infecting the USB device was programmed to tell the system that it was compromising the controller... an unlikely scenario.

Copying New Firmware:
* As with the Anti-Virus question, the system cannot see past the controller.
* When you update firmware on a USB device, the new firmware is loaded into memory, then the controller is responsible for overwriting its old firmware and reporting back to the system with the new firmware status.
* If I was writing BadUSB malware, the first thing I would to would be to disable that process: Allow the controller to copy the new firmware to memory, then strip off the revision number of the new firmware and report THAT to the system.
-- The system thinks it has new firmware, but the malware is still there.

Making USB devices unprogrammable:
* This is the most likely solution, but there are two MAJOR problems
1. It doesn't fix the BILLIONS of USB devices that are already in the wild.
2. If a manufacturer ever discovers a problem with their firmware (say, an exploit) there is no way to patch it.

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