Definition of CryptoLocker

CryptoLocker is a type of ransomware, a malicious software that encrypts the victim’s files, making them inaccessible. It then demands payment, typically in the form of cryptocurrency, to decrypt and restore access to the files. CryptoLocker became particularly notorious in 2013, as it was one of the first instances of ransomware to extort a significant number of users globally.


The phonetic pronunciation of the keyword “CryptoLocker” is:K-R-IH-P-T-O-U-L-AH-K-E-R

Key Takeaways

  1. CryptoLocker is a type of ransomware that encrypts the victim’s files, making them inaccessible until a ransom is paid to decrypt them.
  2. It typically spreads through email attachments, malicious downloads, or compromised websites, and often targets specific file types such as documents, images, and videos.
  3. Preventive measures include regularly updating your software, using strong antivirus tools, avoiding suspicious emails and attachments, and regularly backing up your data.

Importance of CryptoLocker

CryptoLocker is important because it represents a significant development in the world of cybersecurity threats.

As a form of ransomware, CryptoLocker targets computer systems by encrypting the victim’s files and demanding a ransom in exchange for the decryption key.

It emerged in 2013 and quickly made its impact known by causing considerable damage to both individuals and organizations; it forced victims to either pay the ransom or face the loss of valuable data.

The notoriety of CryptoLocker highlights the growing sophistication of cybercriminals and serves as a reminder for the need for continuous improvements in cybersecurity measures to protect against evolving threats.


CryptoLocker is a nefarious piece of software that belongs to a category of malware known as ransomware. The primary purpose of CryptoLocker is to infiltrate computer systems, encrypting the victim’s data and rendering it inaccessible without a unique decryption key. The perpetrators behind CryptoLocker then demand ransom payments from the affected users in return for the decryption key, essentially holding their files hostage.

When successfully deployed, CryptoLocker can cause severe damage to users and organizations, as critical business documents, personal files, and other important data can be temporarily or permanently lost if the ransom is not paid. CryptoLocker is typically spread through email attachments and malicious downloads. Additionally, it can propagate through a system’s network, infecting connected devices.

Once it infiltrates a device, the malware uses sophisticated encryption algorithms to encrypt the files and the affected user then receives a ransom demand, typically in the form of a pop-up or browser message. The ransom must be paid within a specified timeframe, usually in the form of cryptocurrencies such as Bitcoin, to minimize the possibility of tracing the criminals. As CryptoLocker continues to plague individuals and organizations worldwide, cybersecurity professionals emphasize the importance of maintaining up-to-date security measures, regular data backups, and user education to mitigate the risk of falling victim to such malicious ransomware attacks.

Examples of CryptoLocker

CryptoLocker is a type of ransomware that encrypts files on the victim’s computer, demanding a payment or “ransom” for the decryption key. Here are three real-world examples of CryptoLocker attacks:

Swansea Police Department (Massachusetts, USA) – In 2013, the Swansea Police Department was targeted by CryptoLocker, which encrypted their important files. Instead of working to remove the ransomware, the department decided to pay the $750 ransom in Bitcoin. This promptly led to the restoration of their files, but also raised questions about the security of government systems and the consequences of giving in to ransom demands.

Small Business Case (North Carolina, USA) – In 2014, a small business owner in North Carolina fell victim to CryptoLocker. In this case, the ransom demand was $500 in Bitcoin to unlock the encrypted files. The owner opted to pay the ransom, and only after receiving the decryption key could they regain access to their critical data.

Tewksbury Police Department (Massachusetts, USA) – Yet another police department, this time in Tewksbury, was attacked by CryptoLocker in early

The department initially refused to pay the ransom of around $500 to restore their files. It later conceded, however, after specialists from the FBI and other cybersecurity experts were unable to help. Like the Swansea case, this occurrence highlighted potential vulnerabilities in public infrastructure.

FAQ on CryptoLocker

What is CryptoLocker?

CryptoLocker is a type of ransomware that encrypts files on the infected computer system and demands a ransom payment for the decryption key. It typically spreads through email attachments, malicious URLs, or compromised networks.

How does CryptoLocker infect a computer?

CryptoLocker can infiltrate your computer when you open an infected email attachment, click on a malicious link, or have your device compromised through a vulnerable network connection. Once it gains access, it will encrypt your files and display a ransom message, demanding payment to decrypt them.

How can I remove CryptoLocker from my computer?

Removing CryptoLocker from your computer requires the use of reliable antivirus or anti-malware software. You should update your security software to the latest version, restart your computer in Safe Mode, and then perform a system scan to detect and remove the ransomware. Note that this process may not recover the encrypted files.

How can I recover my files after a CryptoLocker infection?

Recovering files after a CryptoLocker infection may be possible using third-party decryption tools, however, their success rates may vary. Restoring from a reliable backup is the best method to recover your files. Keep in mind that paying the ransom does not guarantee a decryption key will be provided by the attacker.

How can I prevent CryptoLocker infections?

To prevent CryptoLocker infections, practice good security habits such as keeping your operating system and software up to date, using a reliable antivirus/anti-malware program, avoiding suspicious email attachments and links, and regularly backing up your files to an external storage device or cloud service.

Related Technology Terms

  • Ransomware
  • Encryption
  • Bitcoin
  • Malware
  • Data Recovery

Sources for More Information


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