Microsoft helps law enforcement get around encryption

by Nancy Gohring

April 30, 2008 —

The growing use of encryption software -- like Microsoft's own BitLocker
-- by cyber criminals has led Microsoft to develop a set of tools that law enforcement
agents can use to get around the software, executives at the company said.

Microsoft first released the toolset, called the Computer
Online Forensic Evidence Extractor (COFEE), to law enforcement last June
and it's now being used by about 2,000 agents around the world, said Anthony
Fung, senior regional manager for Asia Pacific in Microsoft's Internet Safety
and Anti-Counterfeiting group. Microsoft gives the software to agents for free.

While Microsoft can point to wide usage of COFEE, some experts are skeptical
about using that type of tool to recover data, and even the developer of the
product at Microsoft acknowledges that it's not accepted by some users.

Fung, who initiated the creation of COFEE, spent 12 years as a police officer
in Hong Kong, with the final seven dedicated to fighting cybercrime. When he
joined Microsoft, he sought to devise a way that agents could do better at finding
valuable information on computers used by cyber criminals.

When he was an officer, the protocol for handling computer crime was to remove
a computer from the scene of the crime, taking it back to the lab where computer
scientists would search it for information. In many regions of the world this
is still the standard procedure. "At that time everybody followed that
principle, but they knew that once they unplugged the computer, which was the
guideline, a lot of potential information was lost," Fung said.

That's because data on an encrypted system is accessible to police so long
as the criminal has logged on and the PC remains on. But if police shut the
system down, they need to have the criminal's password to get past the encryption
software when the computer boots back up. The release of Vista has accelerated
the problem because BitLocker, a data encryption feature, comes with Windows
Vista Enterprise and Ultimate versions, Fung said.

"Criminals are taking advantage of these technologies like BitLocker,"
Fung said. "BitLocker was the real driving force because it's becoming
ubiquitous." In addition to BitLocker, other hard disk encryption methods,
like one from PGP, also frustrate agents, he said.

While COFEE doesn't break BitLocker or open a back door, it captures live data
on the computer, which is why it's important for agents not to shut down the
computer first, he said.

COFEE is a set of software tools that can be loaded onto a USB drive. Brad
Smith, general counsel at Microsoft, called it a "Swiss Army knife for
law enforcement officers," because it includes 150 tools. A law enforcement
agent connects the USB drive to a computer at the scene of a crime and it takes
a snapshot of important information on the computer. It can save information
such as what user was logged on and for how long and what files were running
at that time, Fung said. It can be used on a computer using any type of encryption
software, not just BitLocker.

Previously, an officer might spend three or four hours digging up the information
manually, but COFEE lets them do it in about 20 minutes, he said.

Still, COFEE has its foes. Some experts say that running any program causes
memory contamination that affects the data agents are looking for on the computers.
"Any time you're touching a live computer you're changing it in some way,"
said Chris Ridder, a residential fellow at the Stanford Center for Internet
and Society.

One reason some agents prefer to take the computer back to the lab and create
an exact image of it is because they can later compare that image to the actual
computer. "You've got the original computer locked away in an evidence
safe somewhere, so if someone questions the integrity of the image you can verify
it against the original," he said.

Agents can't compare data that they collect on a live machine at a crime scene
with the computer later because the act of powering down the machine changes
it, he said.

Ridder, who was not familiar with COFEE specifically, also worries that any
forensic software is vulnerable to hacking. "A forensic software maker
needs to be very careful to make their software as resistant to tampering as
possible," he said. He wrote
a paper last year about vulnerabilities in forensic software.

Rather than take the risk of tainting evidence by using products like COFEE,
authorities have alternatives. They can get court orders permitting them to
hack into a password-protected file or they may be able to convince a defendant
to disclose the password, Ridder said.

Microsoft's Fung said the use of software like COFEE depends on the laws and
regulations of countries that may forbid its use. "It's based on their
principles and what is required from the court," he said.

Ridder finds it ironic that Microsoft built BitLocker and is now providing
law enforcement agents with ways to get around it. "Maybe Microsoft should
spend its efforts making BitLocker more secure," he said. For example,
maybe users should have the option of requiring a password that allows access
to a USB drive. While some users might find that onerous, others might like
to have the option, he said.

He also suggested that BitLocker and other encryption products probably aren't
as widely used as Fung suggests -- by cyber criminals or honest computer users.
Many people are reluctant to use them because they can slow down a computer
or because they worry they might forget their passwords. "My sense is it's
not nearly as big a threat as they would suggest," he said.

Agents in 15 countries including Poland, the Philippines, New Zealand and the
U.S. are using COFEE, Microsoft said. In New Zealand, a forensics examiner recently
used COFEE to find evidence that led to the arrest of an individual involved
in trading child pornography, said Smith.

Smith and others spoke on Monday at the start of a three-day conference Microsoft
is hosting for law enforcement officials at its Redmond, Washington headquarters,
inviting U.S. and international police, prosecutors and representatives from
agencies like the Federal Bureau of Investigation. Microsoft has been hosting
the conferences, which invite feedback from the law enforcement agents, since
2006, Smith said.

(Robert McMillan in San Francisco contributed to this report. )

IDG News Service