Ransomware is a pesky type of cyberattack that has the potential to
cause a large loss of data and disrupt critical business functions.
Hackers use ransomware as a means
of extortion and can be tricky to eliminate. Sometimes used for
political coercion, but most often for personal gains, ransomware can
present a really annoying problem.
Ransomware Defined: A Brief Overview of Ransomware Attacks
Ransomware
is a form of malware that functions by prohibiting access to a device
or dataset. A merging of the terms ransom and software, the intended
purpose is to prevent a person from accessing systems or files in
exchange for a ransom. Today, that
ransom is typically requested in the form of electronic payment or
cryptocurrency.
These “hostage” situations have become more and
more costly for organizations. This is not only because of the cost of
the ransom, but also the cost of replacing old systems and recovering
from lost functionality and operations.
Hackers are also becoming
more adept at their trade and are both demanding ransoms for renewed
access and extorting funds by threatening to go public with the data
they’re holding. Forbes reports that ransomware payouts more than doubled in Q4 2019, making this a more prominent threat than previously seen.
How Does Ransomware Work and Spread?
Ransomware works by
infecting a system and thus limiting access to its programs or files.
Ransomware can infect a system through multiple channels:
- Spam Email:
Most often, ransomware is delivered via a spam email that infects the
system when a link is clicked or an attachment is opened. When users
click on the offending file, the ransomware is downloaded to their
systems.
- Malvertising: This is when a user clicks on a fake ad that downloads the ransomware.
- Chat Messages: Ransomware can also be spread through users clicking on links in chat messages in various apps or even social media messages.
- Social Engineering: Hackers gain passwords and other information to help them access systems and plant ransomware.
Most
often, ransomware is an executable file that often tries to masquerade
as harmless in a zip folder or by impersonating a legitimate file. Basic
ransomware requires human action, while other more sophisticated
ransomware attacks are able to spread without any human intervention.
Once on a machine, ransomware begins its work encrypting data to make it
inaccessible or removing the user’s access to files.
Types of Ransomware
Hackers
have a choice as to what they’d like to hold hostage when it comes to
these infections. In general, there are two types of ransomware:
- Crypto Ransomware:
Crypto ransomware encrypts files or specific programs to block access
to particular software. In this scenario, users can still access a
device, but they are locked out of the encrypted program or files.
- Locker Ransomware: Locker ransomware refers to an infection that locks access to a device or system, making all system components inaccessible.
According to Deloitte, crypto ransomware is more prevalent and accounts for 64% of ransomware attacks, compared to 36% for locker ransomware.
Subsets of ransomware include the following:
- Scareware:
Scareware is a subset of locker malware that impersonates antivirus or
malware removal software. Hackers use scareware to “scare” users into
believing their systems have been compromised. At that point, hackers
try to solicit money to remove the fake malware and then attempt to
actually infect the systems.
- Doxware: Doxware
refers to a type of ransomware attack that is successful in obtaining
sensitive information in addition to locking the device/dataset. Hackers
demand ransom in exchange for not posting sensitive information for
public viewing.
- Mobile Ransomware: As the name
implies, this type of ransomware is targeted to mobile devices in an
attempt to obtain sensitive information or prevent a user from opening
their device.
Significant Ransomware Attacks: A Stroll Down Ransomware Memory Lane
Ransomware
attacks can be costly. Similar to real-life hostage situations, law
enforcement always recommends not negotiating. That said, sometimes it
makes more financial sense to organizations to engage rather than
relent.
Here are some high-profile ransomware examples:
- BadRabbit:
BadRabbit was ransomware that largely impacted Russia and the Ukraine
in 2017. Distributed through a Russian media outlet, the ransomware
attack seemed designed to take down corporate networks related to news.
- CryptoLocker:
First appearing in 2013, CryptoLocker distributes malware through
infected email attachments. It then finds and encrypts files on one
device and spreads throughout the mapped network drives. Through
asymmetric encryption,
the attacker holds the key to unlock the files.
- NotPetya:
NotPetya was a ransomware attack that largely affected the Ukraine.
Often attributed to the Russian government, NotPetya was used during
political upheaval and targeted a tax and accounting software site. It’s
believed
to have been an attempt to disrupt financial systems in order to
gain a physical advantage.
- Ryuk: Ryuk
ransomware is unique because it targets large organizations with
critical assets that are often inclined to pay large ransoms. First
discovered in 2018 when it disrupted publications for Tribune
Publishing, Ryuk is often
attributed with abnormally high ransom payments and a fairly
large success rate.
- WannaCry: One of the most significant modern ransomware attacks occurred in 2017. WannaCry
impacted more than 150
countries and upwards of 230,000 users. The health care industry
was hit the hardest, with the ransomware attack affecting more than
one-third of all health trust in the United Kingdom. This attack left a
bill of more than $4 billion worldwide.
How to Prevent and Protect Against Ransomware: Boosting Your Protections
Many types of malware infect your systems through phishing techniques or pop ups. To prevent ransomware attacks only open email attachments or click links if they originate with a trusted source. Also be on the lookout for . Review content and don’t respond if the message seems out of character for spoofed email addressesthe sender.
Keep an eye out for social engineering
tactics, a known skillset for experienced ransomware hackers. Don’t
give out personal details if you have received an unsolicited email or
phone call. Never give out password details, and avoid discussing
personal information with unverified callers.
Other best practices
for avoiding ransomware include regularly updating systems to take
advantage of vulnerability patches and installing reputable virus and
firewall protections. Also, avoid using public Wi-Fi networks.
Finally,
a robust backup and recovery strategy can reduce the risk that comes
from ransomware. While most companies have a backup plan in place, it is
important for backups to be comprehensive across all devices and
performed regularly.
How to Remove Ransomware: Effective Methods for Combatting Malware
Removing
ransomware is no easy feat. Reversing file encryption is almost
mathematically impossible without the encryption key that is held in
stead by the bad guys. Occasionally a decryptor can be used to crack the
offender, but more often than not, you have to take the approach of
removing the ransomware with the understanding that you may be
sacrificing your data.
To fully remove the ransomware, you will
likely have to restore a clean backup. While you may lose data, this
could be the only removal strategy to prevent the spread to other files.
What’s the Difference Between Ransomware vs. Malware vs. Social Engineering vs. Phishing?
Ransomware, malware, social engineering and phishing all encompass different forms of ill-intentioned cyberattacks.
- Malware is a general term formed by the words “malicious” and “software” that
describes different types of software intended to compromise systems,
obtain sensitive data or gain unsanctioned access to a network.
- Ransomware
is a category of malware where attackers use various methods to encrypt
your data, making it inaccessible, or bar you from entry to a
particular system or device. Attackers then demand a ransom in exchange
for reinstating your access.
- Social Engineering by contrast, is a method used to extract sensitive details by way of
human manipulation. With social engineering, hackers connect with users
while pretending to represent a legitimate organization and seek to
ascertain critical information such as account numbers or passwords.
- Phishingis a form of social engineering that involves email, phone, text or
illegitimate websites. In both instances, the collected information is
used to access protected accounts or data.
While our guide acts as an introduction into the threats posed by
ransomware, this is by no means an exhaustive list. Ransomware and the
cybersecurity world change on a daily basis, and attacks are becoming
increasingly sophisticated. The best way to
combat cyberattacks is to stay informed about the latest attacks.
Comments
Post a Comment