Ransomware, Crypto-Malware, and, Logic Bombs#

In today’s digital landscape, cybersecurity threats continue to evolve at an alarming rate, posing significant risks to individuals, businesses, and organizations worldwide. Among the various forms of malware, three notorious types have emerged as major concerns: ransomware, crypto-malware, and logic bombs. Recognizing the indicators associated with these threats is crucial for proactive defense and safeguarding against potential cyberattacks. This article discusses the basic characteristics of ransomware, crypto-malware, and logic bombs, their real-world examples as well as the protective measures that can be implemented as a defense against these malicious threats.

What is Ransomware?#

Ransomware is a type of malicious software designed to encrypt files and data on a victim’s computer or network, rendering them inaccessible until a ransom is paid. The encryption used by ransomware is often strong and virtually impossible to break without the decryption key, leaving victims with limited options for recovering their data. Ransomware typically displays a ransom note on the victim’s screen. This note contains instructions on how to pay the ransom, usually in cryptocurrency, in exchange for the decryption key.

In some cases, the only way to restore the system is by rebuilding it entirely. Rebuilding involves wiping the infected system clean and reinstalling the operating system and applications from scratch which can be a complex and time-consuming process.

Examples of Famous Ransomware Attacks#

CryptoLocker#

Cryptolocker emerged in 2013. It is a trojan horse that uses asymmetric public key encryption to encrypt files on the victim’s system. This encryption method uses two keys i.e. a public key and a private key. Hackers encrypt victim’s data using the public key. This encrypted data can then only be decrypted using the private key held by them. By employing the robust RSA 2048-bit encryption algorithm, data recovery becomes exceedingly improbable without the corresponding key.

NotPetya:#

NotPetya was a ransomware attack that occurred in 2017. The primary goal of this worm was causing destruction rather than financial gain. Despite resembling a ransomware attack, the decryption key provision was unreliable, leading to permanent data loss in most cases.

WannaCry:#

WannaCry was a large-scale ransomware attack that occurred in 2017, affecting organizations worldwide. It capitalized on a Windows operating system vulnerability referred to as EternalBlue. WannaCry propagated rapidly across networks, encrypting files and demanding a ransom for decryption. It caused widespread disruption in sectors like healthcare, transportation, and government.

What is Crypto-Malware?#

Cryptocurrency mining is the process of validating and adding new transactions to a blockchain network, as well as generating new units of a cryptocurrency as a reward. It involves utilizing computational power to solve complex mathematical problems, which helps maintain the security and integrity of the blockchain. Cryptojacking, also known as malicious crypto mining, is a theft-of-services attack. It involves the unauthorized use of an individual’s or organization’s computing resources to mine cryptocurrencies. Crypto-malware is a malicious tool used to execute cryptojacking attacks. It enables them to harness the victim’s computer processing power for resource-intensive calculations. Consequently, the victim experiences diminished performance and prolonged response times on their system.

Examples of Famous Crypto-Malware-based Attacks#

Coinhive#

Coinhive was one of the most well-known and widespread crypto-malware-based attacks. It emerged in 2017 as a JavaScript-based mining service that website owners could integrate into their sites. The idea was to use visitors’ CPU power to mine the Monero cryptocurrency while they browsed the website. However, Coinhive’s mining script was often implemented without the knowledge or consent of the website visitors, making it a form of unauthorized cryptojacking. Numerous websites, including legitimate ones, unknowingly became part of the Coinhive network, leading to significant performance degradation for visitors.

Smominru#

Smominru is a massive cryptojacking botnet that has been active since 2017. It exploits the EternalBlue vulnerability in Windows-based systems to infect them with crypto-malware. Once a system is compromised, the malware takes control and starts mining the Monero cryptocurrency using the victim’s computing resources.

What is a Logic Bomb?#

A logic bomb is a form of malicious software planted by an authorized user, often a disgruntled employee, within a company’s network. It remains dormant within the system until it is triggered by a specific event or condition. One instance of this is when a network administrator installs and configures a logic bomb that is designed to erase the entire company database if their employment is terminated. The logic bomb software can employ various triggers to activate its payload execution, such as specific dates or times or when a user performs a particular action. Another term for this type of logic bomb is a “time bomb.” In certain cases, compromised systems are equipped with logic bombs to activate if forensic activities are detected, leading to the deletion of all digital evidence. This thwarts the success of the investigation team and aids the concealment of the attacker’s identity and methods.

Example of Famous Logic Bomb Attacks:#

UBS Paine Webber#

Roger Duronio, a former IT employee at UBS Paine Webber, planted a logic bomb in the company’s network. On March 4, 2002, the logic bomb was triggered, causing a distributed denial-of-service (DDoS) attack. It affected approximately 2,000 servers at UBS PaineWebber. In 2006, he was sentenced to over eight years in prison and fined over $3 million.

Time-Based Logic Bomb Attack on South Korea#

In March 2013, South Korea fell victim to a malicious time-based logic bomb attack. The primary targets of this attack were banks and media companies, which suffered severe consequences as their hard drives were wiped clean.

How to defend against Ransomware, Crypto-Malware, and Logic Bombs?#

  • Keep your software’s security patches up to date.

  • Use host-based antimalware software and ensure the signatures are up to date.

  • Use spam filters for your e-mail.

  • Never open/download attachments from unknown sources.

  • Carefully inspect email senders, subject lines, and email content for any suspicious or unexpected elements.

  • Be very careful about visiting unfamiliar or shady websites.

  • Use browser extensions or ad blockers specifically designed to block malicious scripts from running on your device.

  • Implement clear separation of duties among employees involved in critical systems and processes. This makes it more challenging for a single person to carry out a logic bomb attack without detection.

  • Implement strict authorization and approval processes for making changes to systems, code, or configurations.

  • Implement employee monitoring and auditing systems to detect any suspicious activities or unauthorized attempts to modify systems or code.

  • Implement a robust backup and recovery program. It will ensure timely backups and facilitate the restoration of your data and systems to a previous, uncompromised state. This minimizes the impact of a ransomware/logic bomb attack and helps you to recover quickly without paying the ransom or suffering data loss.

Conclusion:#

The utilization of ransomware, crypto-malware, and logic bombs in cyber attacks can result in severe repercussions for both individuals and organizations. To effectively safeguard against these threats, it is crucial to implement a comprehensive range of security controls as outlined in the preceding section.