I work in the field of IT security and even I can be surprised by
the creativity and ingenuity of attackers looking to make a quick dollar. Enter CrytoLocker, a particularly nasty piece
of malware that encrypts Windows –based files on both network drives and localfile systems. The strong encryption used
makes it virtually impossible for people to recovery their data unless they
follow the instructions provided by the attackers asking for money in order to
be provided with the decryption key.
Victims of this ransomware usually experience the infection when
unknown attachments are opened through email or through the use of infections
already on the machine. Occasionally, it
is installed via drive-by downloads.
Word, Excel, PDF, and other daily-use file types (including pictures and
movie files) are susceptible to this attack.
Ransomware attackers then present a screen to their victims stating that
they must pay $300 in order to receive the key or their files will all be
deleted forever within 72 hours.
Unfortunately, aside from losing $300, many times the decryption does
not work and the files are lost anyway.
This is a very good example of why people need to backup their critical
files!
Anti-virus software is unable to prevent this malware from
infecting machines, too, meaning even people who are diligent with their A/V
software are vulnerable. The most common
infections have come in through email attachments, but the malware has also
piggybacked on existing malware, such as Zeus.
The best way to prevent an infection in this case is the actively ensure
your anti-virus is up to date and that it scans daily to circumvent the
infection of these other Trojans.
Email attachments are something people have been warned against
for years, yet this is still one of the most popular avenues for infecting
machines. Phishing scams are a great way
for attackers to hit hundreds of people at once, through specially crafted
emails that look like they came from legitimate organizations. Always double check that any email you
receive from a shipping organization, a bank, or any other common source is
legitimate. Check the email return
address to ensure that the domain is correct, and call the company to find out
if what they are ‘selling’ is in fact truth.
Be aware of which company is shipping your packages so that you only pay
attention to emails from them (and even then, scrutinize its content for
accuracy before you click any attachments or links). Question your bank before you respond to an
email to find out whether this is their normal process for conducting
business.
CrytoLocker is a dangerous piece of malware, so protect yourself
from it as best as you can. Imagine how
it would feel to be locked out of your computer, potentially never accessing
your important files again. Back up your
data regularly, and unplug that backup from the network or computer when you
are finished. This is, along with
current antivirus software and due diligence, is your best defense.