Schedule

Schedule

Wednesday, May 27

1432767600 Tech News 2Night
1432769400 Android App Arena
1432774800 Ham Nation

Thursday, May 28

1432827000 Tech News Today
1432830600 TWiT Live Specials
1432839600 Know How...
1432846800 Home Theater Geeks
1432854000 Tech News 2Night

Friday, May 29

1432918800 Tech News Today
1432922400 This Week in Law
1432933200 Before You Buy
1432940400 Tech News 2Night

Saturday, May 30

1433008800 The Tech Guy

Sunday, May 31

1433095200 The Tech Guy
1433109600 This Week in Tech

Monday, June 1

1433178000 Tech News Today
1433181600 Triangulation
1433187000 iOS Today
1433194200 Coding 101
1433199600 Tech News 2Night

Tuesday, June 2

1433264400 Tech News Today
1433268000 MacBreak Weekly
1433277000 Security Now
1433286000 Tech News 2Night
1433289600 All About Android

Wednesday, June 3

1433345400 FLOSS Weekly
1433350800 Tech News Today
1433354400 Windows Weekly
1433361600 This Week in Google
1433372400 Tech News 2Night
1433374200 Android App Arena
1433379600 Ham Nation

Thursday, June 4

1433437200 Tech News Today
1433440800 Know How...
1433451600 Home Theater Geeks
1433458800 Tech News 2Night

Friday, June 5

1433523600 Tech News Today
1433527200 This Week in Law
1433538000 Before You Buy
1433545200 Tech News 2Night

Saturday, June 6

1433613600 The Tech Guy

Most Recent Episodes

FLOSS Weekly
Episode #338: Lucee May 27th, 2015

Andrew Dixon, Gert Franz, and Lucee: a dynamic scripting language for the JVM.

Tech News Today

iPhones crash and reboot when a specific string of text is received.

All About Android

Google IO predictions, Periscope for Android, and a a packed round table session.

Security Now
Episode #509: TLS Logjam May 26th, 2015

Routers with a USB port could be vulnerable to attack because of a NetUSB bug.

Tech News 2Night

Mashable's Jason Abbruzzese talks Charter/TWC merger

MacBreak Weekly

Jony Ive promoted to 'Chief Design Officer'

Tech News Today

Jony Ive has been promoted to Apple's Chief Design Officer.

This Week in Tech

Uses of VR, Key FOB security, new Spotify, @POTUS, and more.

The Tech Guy
The Tech Guy 1190 May 24th, 2015

Make your own media player.

The New Screen Savers

Delighting audiences for decades, our guest Martin Sargent

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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