The Register® — Biting the hand that feeds IT

Feeds

Stolen laptops hand hackers keys to the kingdom

Peril of purloined PCs

Cloud based data management

Infosec As web apps are becoming more secure stolen laptops have become among the easiest ways to break into corporate networks. High profile firms such as Fidelity and Ernst and Young along with celebrities such as Kevin Costner have lost laptops over recent months. Concern over these thefts has focused on the exposure of data left on these devices. But the potential to use stolen kit to lift user credentials also poses a grave risk.

During a presentation at Infosec on Tuesday, penetration testing firm SecureTest explained how DIY hardware devices or software available for purchase from eBay might be used to reset or circumvent passwords set in a laptop's BIOS. "If that fails you can always take the drive out and fit it with a USB connector," explained SecureTest's Rob Pope.

A Linux tool called Backtrack, which can run from a CD loaded onto a Windows PC, might then be used to get system keys and password hashes. Windows stores the hashes of passwords derived from the LM algorithm instead of directly storing passwords. But LM encryption is weak and susceptible to brute force attack using Rainbow Crack or other tools.

SecureTest pre-computed a rainbow table of password hashes totaling 19GB. Thereafter obtaining the plain text of a password becomes a simple job of matching password hashes. Most of the hacker tools in this area are American so the inclusion of a pound sign in passwords is capable of frustrating attacks.

Next up SecureTest showed how a program called Disk Investigator might be used to extract the encrypted form of WEP key passwords or remote desktop login credential from a Windows Registry file. It showed how a program called Cain was able to decode Cisco VPN client passwords given access to a purloined corporate PC. "What we find during penetration testing is that most passwords are based either around the Lord of The Rings, the names of planets or Star Wars," said Pope.

SecureTest md Ken Munro outlined a number of defences firms might employ against the attacks the firm highlighted. Although not foolproof, use of BIOS passwords is a significant barrier against attack. Firm should avoid setting up machines that can be booted from USBs, floppy discs, CD ROMs or from a network. Strong passwords contained a mix of alphanumeric characters should be used. Finally firms should implement either disc encryption or, at minimum, the encryption of sensitive files, Munro advised. ®

Regcast training : Hyper-V 3.0, VM high availability and disaster recovery

More from The Register

Samsung Galaxy Note 8: Proof the pen is mightier?
Sammy’s iPad Mini killer has a stylus to stab other rivals too
Microsoft lures buy-curious vixens, corduroys with a cheap fondle
Surface slab sales latest: Will no one rid Ballmer of these turbulent tabs?
First look: iOS 7 for iPad
No, Apple hasn't released it yet, but that doesn't stop intrepid devs
 breaking news
Curtain drops on Apple Store ahead of WWDC: What lies behind?
Steve Jobs watching from on high. No pressure, lads
 breaking news
Cold, dead hands of Steve Jobs slip from iPhones: The Cult of Ive is upon us
Billionaire biz baron's death clears way for uber-shiny iOS 7
Airbus imagines suitcases that find themselves
Point your mobe at your smalls to track their every move
Surprise! Intel smartphone trounces ARM in power trials
Tests show equal performance while sipping significantly less juice
Samsung plans LTE Advanced version of Galaxy S4
1Gbps download capability could stiffen drooping S4 sales forecasts
Apple said to be 'exploring' 5.7-inch iPhone
Who's the copycat this time, Mr. Cook?