Ransomware

Top 5 Security Threats to Be Careful

Learn about common security threats: ransomware, insider threats, phishing, cloud attacks and malvertising, with plain steps to reduce each risk.

Updated 7 Min Read

Security threats come in many forms, and five of the most common are ransomware, insider threats, phishing, cloud attacks and malvertising. Each one can lead to data loss, stolen credentials or lost trust. This post explains how each threat works, what each attack looks like and which simple steps help reduce the risk.

What are the main security threats?

The proliferation of technological infrastructures with digitalization meets the needs of institutions and leads to an increase in cyber security gaps and thus security threats. The possible risks are listed as follows and the analyses made in recent years.

What is Ransomware?

Ransomware is malware that prevents a user from accessing their computer and critical files, thereby demanding ransom. The threat actors’ desire to generate large amounts of revenue in a short time leads to an increase in ransomware threats since its distribution and use do not require technical skills.

In ransomware attacks, files within the scope of assets to be protected for the person/organization are encrypted, and the user is prevented from using these files. In addition, payment is made in virtual currency to recover sensitive data and prevent it from being shared publicly. If the victims don’t pay the ransom, sensitive data will be lost and shared publicly.

What are the current ransomware trends?

Double Extortion

When ransomware first appeared, it encrypted files with various encryption algorithms and deleted them from the target system to demand a ransom payment. However, threat actors are developing new methods for institutions that realize the ransomware threats and make the necessary backups. One of them is called Double Extortion.

Threat actors not only encrypt files but also leak data from the target system, threatening to publish or sell it publicly.

Triple Extortion

The latest trend that ransomware groups are starting to use is the Triple Extortion method. The main goal is to pressure targets to pay the ransom.

In Triple Extortion, in addition to the ransomware encrypting files and leaking them from the target system (Double Extortion), DDoS attacks are carried out on the network infrastructure of the target organization. This trend of attacks will also indirectly affect victims’ assets such as users, clients, and service providers.

Double and triple extortion
Pressure usedDouble extortionTriple extortion
Files are encryptedYesYes
Data is leaked from the targetYes, with a threat to publish or sell itYes, as in double extortion
DDoS attacks on the networkNoYes, on the target organization’s network infrastructure

Which ransomware attacks and actors are well known?

  • Acer
  • Colonial Pipeline
  • Kaseya
  • Lockbit2.0
  • Conti
  • Darkside
  • REvil
  • Ragnar

How do you protect yourself from Ransomware?

  • Keep regular backups of your assets that need to be protected in environments without internet access.
  • Train your staff against common phishing attacks.
  • Use IDS/IPS systems that can block existing hacking attempts.
  • Upgrade used apps to the latest version.

What are Insider Threats?

It is a common type of attack that can occur intentionally or unintentionally within the framework of corporate personnel and negatively affects corporate reputation. It can be done for financial gain, or sensitive data can be leaked if the relevant security procedures are not followed.

Post on an underground crime forum seeking insider threat collaboration
Figure 1: Post for Insider Threat collaboration on the underground crime forum

Insider threats can harm the organization through the situations listed below:

  • Espionage
  • Terrorism
  • Disclosure of information
  • Sabotage
  • Intentional or unintentional loss or degradation of department resources or capabilities
Definition: Insider threatCISA defines an insider threat as the threat that an insider will use authorized access, wittingly or unwittingly, to do harm to the department’s mission, resources, personnel, facilities, information, equipment, networks, or systems.

How do you protect from Insider Threats?

  • Employees should train on security processes.
  • Access to sensitive data should be restricted.
  • Double factor protection should be used in the systems used.
  • Check the history of employees, especially those who need access to sensitive data.

What is Phishing Attack?

Phishing is a social engineering attack that is often used to obtain user data, including login credentials and credit card numbers. Attackers try to persuade users to click on a link that could download malware or redirect them to a dangerous website.

In the phishing methods, which constitute the first stage of almost every cyber attack, the targets are tried to be deceived by the attackers with fear, anxiety, or offers that are too tempting to be true. In addition to the abuse of such feelings, phishing attacks can organize through copies of actual documents.

Phishing email with a fake phone billing document
Figure 2: Example of a phishing email with fake phone billing document
How a phishing attack runs
  1. Deceive the targetFear, anxiety or a tempting offer, or a copy of a real document.Technique T1566 (MITRE ATT&CK, opens in a new tab)
  2. Persuade a clickThe user is persuaded to click a link.
  3. Harm followsMalware is downloaded or the user lands on a dangerous website.

How do you protect from Phishing Attacks?

  • Emails and links from unknown sources should not be respected.
  • Suspicious messages should be cleared from the platforms used.
  • Network intrusion detection systems and email transmission paths can be used to detect phishing emails containing malicious email attachments. The solutions that can use for this can be signature or behavior-based. In addition, DKIM+SPF checking or filtering based on email header analyzes can give details about possible attack attempts.
  • Using anti-virus solutions on the email server or user computer can help detect malicious files and attachments. In addition, it can be helpful to monitor sub-processes created by software associated with Microsoft Office or other documents.

What are Cloud Attacks?

The popularity of the concept of cloud computing is being used more and more widely thanks to big players such as Amazon, Google, and Microsoft that provide cloud computing platforms. This process, which generally starts with backup, is included in the companies’ storage, sharing, and information processing processes along with the needs.

Also, as cybersecurity experts know, anything that becomes popular in the digital world will inevitably become the target of malicious cyber actors.

What types of cloud attacks exist?

  • Denial of Service (DoS) Attacks
  • Malware Injection Attack
  • Side-Channel Attack
  • Network-based co-residence check
  • Brute forcing
  • Authentication and MiTM Attack
  • Hypercall Attacks
  • Hyperjacking
  • Exploiting Live Migration

How do you protect from Cloud Attacks?

  • Cloud users must ensure that the data stored in the cloud is encrypted and keep the key securely, as they lose a great deal of control over the hosting process after moving their data to remote servers.
  • Detect side-channel attack only during the deployment phase. It can be done by collecting records for start and stop machines and importing them into a SIEM solution.
  • A large number of new machines appearing and shutting down in a defined time may indicate that an attacker is performing unusual activities.
  • Instead of simple username and password verification control, strong password creation policies should be established, and multi-factor authentication should be implemented.

What are Malvertising Attacks?

Malware has long been one of the attack vectors used by threat actors. Attackers now use malicious ads to appear more legitimate to their targets, thereby infecting target systems with malware.

With this technique, attackers redirect users to malicious websites or inject code into advertisements that will directly install malware on the device. The malicious ads used can be difficult to spot as they are paid through legitimate ad providers.

How do you protect from Malvertising Attacks?

  • Ad blockers and script execution blocking browser plug-ins can be used to prevent malicious content distributed through advertisements and the use of JavaScript during exploitation.
  • Firewalls can perform reliability-oriented queries on the URLs that the user wants to visit, including checks such as the registration date, the number of visitors, and the history of malicious activity.
  • IDS systems are used on network discovery, browser identification, etc. It can detect malicious scripts such as exploit codes and common hiding techniques of these codes.
Malvertising ad showing a fake warning message
Figure 3: Malvertising ad showing fake warning message

Conclusion

Organizations that adopt digitalization with rapidly developing technologies can significantly reduce the threats against them without creating an excellent cyber security infrastructure and implementing audit policies.

We aimed to create reference points so that you can find the steps that can be taken to reduce the attack vectors with an overview of the cyber threats that may be against every institution/organization regardless of the sector.

References

Frequently Asked Questions.

What are the most common security threats?

This post covers five: ransomware, insider threats, phishing, cloud attacks and malvertising.

What is double extortion in ransomware?

Attackers both encrypt files and steal data, then threaten to release the stolen data if the victim does not pay. CISA's ransomware guide describes this as pressuring victims by threatening to release stolen data.

What is an insider threat?

CISA defines it as the threat that an insider will use authorized access, wittingly or unwittingly, to do harm to an organization's mission, resources, people, information or systems.

How can I protect myself from phishing?

Avoid clicking links in unsolicited emails, verify requests directly with the organization, and turn on multifactor authentication. The post also advises filtering email and checking sender authentication.

How do I reduce ransomware risk?

Keep offline backups, train staff to spot phishing and keep software up to date. CISA advises testing backups and patching internet-facing servers first.

Sources

  1. 1 CISA: Defining Insider Threats
  2. 2 CISA: Avoiding Social Engineering and Phishing Attacks
  3. 3 MITRE ATT&CK: Phishing (T1566)
  4. 4 CISA: #StopRansomware Guide