We were the first to discover Ransomware :-) way back about half a year
or more ago

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Winterlight
Sent: Monday, April 17, 2006 4:27 PM
To: [email protected]
Subject: [H] Ransomware


http://www.foxnews.com/story/0,2933,187845,00.html

Computer Virus Demands Ransom for Encrypted Files
Wednesday, March 15, 2006
By Ryan Naraine

Virus hunters have discovered a new Trojan that encrypts files on an 
infected computer and then demands $300 in ransom for a decryption
password.

The Trojan, identified as Cryzip, uses a commercial zip library to store

the victim's documents inside a password-protected zip file and leaves 
step-by-step instructions on how to pay the ransom to retrieve the
files.

It is not yet clear how the Trojan is being distributed, but security 
researchers say it was part of a small e-mail spam run that successfully

evaded anti-virus scanners by staying below the radar.

While this type of attack, known as "ransomware," is not entirely new,
it 
points to an increasing level of sophistication among online thieves who

use social engineering tactics to trick victims into installing malware,

said Shane Coursen, senior technical consultant at Moscow-based
anti-virus 
vendor Kaspersky Lab.

The LURHQ Threat Intelligence Group, based in Chicago, was able to crack

the encryption code used in the Cryzip Trojan and determine how the
files 
are encrypted and the payment mechanism that has been set up to collect
the 
$300 ransom.




According to a LURHQ advisory, Cryzip searches an infected hard drive
for a 
wide range of widely used file types, including Word, Excel, PDF and JPG

images.
Once commandeered, the files are zipped and overwritten by the text: 
"Erased by Zippo! GO OUT!!!"
The Trojan then deletes all the files, leaving only the encrypted file
with 
the original file name, followed by the "_CRYPT.ZIP" extension.
A new directory named "AUTO_ZIP_REPORT.TXT" is created with specific 
instructions on how to use the E-Gold online currency and payment system
to 
send ransom payments.

The instructions, which are marked by misspellings and poor grammar, 
contain the following text: "Your computer catched our software while 
browsing illigal porn pages, all your documents, text files, databases
was 
archived with long enought password. You can not guess the password for 
your archived files - password lenght is more then 10 symbols that makes

all password recovery programs fail to bruteforce it (guess password by 
trying all possible combinations)."

The owner of the infected machine is warned not to search for the
program 
that encrypted the data, claiming that it simply doesn't exist on the
hard 
drive.

"If you really care about documents and information in encrypted files
you 
can pay using electonic currency $300," the note says. "Reporting to
police 
about a case will not help you, they do not know password. Reporting 
somewhere about our E-Gold account will not help you to restore files.
This 
is your only way to get yours files back."

The Trojan author uses scores of E-Gold accounts simultaneously to get 
around potential shutdowns, according to LURHQ, which published the 
complete list of E-Gold accounts in the advisory.

Officials from E-Gold, which operates out of the Caribbean island of
Nevis, 
were not available for comment.
"Infection reports are not widespread, so it is not believed this is a
mass 
threat by any means," LURHQ said.
However, the company said social engineering malware is typically more 
successful when it is delivered in low volume to get around anti-virus 
detections.
"[M]ore attention means the likely closing of the accounts used for the 
anonymous money transfer," LURHQ said.


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