What do you do if you get a CryptoLocker?

Ransomware attacks like CryptoLocker can be terrifying. Your personal files are encrypted and held for ransom by cybercriminals who demand payment to decrypt them. If you become a victim, it’s important to stay calm and take the right steps to deal with the attack.

Table of Contents

What is CryptoLocker?

CryptoLocker is a type of ransomware – malicious software that encrypts files on infected devices and demands payment for decryption. It has been around since 2013 and has affected many individuals and organizations.

CryptoLocker is distributed through infected email attachments, compromised websites, and malware downloads. Once installed, it encrypts files like documents, photos, videos, etc. using strong encryption. It even encrypts files on connected devices like external hard drives.

Encrypted files are rendered inaccessible. The attackers display a ransom note demanding payment, usually in Bitcoin, to receive the decryption key. The ransom amounts typically range from $200-$1000 or more.

If the ransom is not paid, the criminals threaten to delete encryption keys, making it nearly impossible to ever recover encrypted files. However, even if you pay, there is no guarantee you will get the decryption key.

How does infection occur?

CryptoLocker spreads through several infection vectors:

Phishing emails with infected attachments like Word docs or zip files. Opening these triggers the malware.
Infected websites – Criminals compromise websites and plant malware that silently infects visitors.
Exploit kits – These are toolkits that probe for security holes in browsers/apps to drop malware. Often seeded on malicious sites.

Botnet infections – Compromised computers are commandeered into botnets which spew malware, including CryptoLocker.
Fake applications – Pirated or cracked apps seeded with malware.
USB drives – Infected drives auto-run malware when plugged in.

Warning Signs of Infection

Here are some signs that may indicate a CryptoLocker infection:

Files becoming corrupted or inaccessible, especially photos, documents, videos, etc.
Programs failing to open files or giving errors trying to access files

Folders containing files disappearing from your directory listing
Computer running very slow
Ransom note appearing on your desktop with payment instructions

If you notice any of these symptoms, there’s a good chance your system is infected with ransomware like CryptoLocker.

What to do if infected?

If you suspect you’ve been hit with CryptoLocker, here are important steps to take:

Disconnect from networks/internet – This prevents the malware from communicating with command servers and infecting other computers.

Determine scope of infection – Check your files, folders, mapped drives, backups, etc. to gauge impact.
Take screenshots – Document ransom note and encrypted files. This provides details for subsequent steps.
Report the crime – Contact authorities to report the attack for investigation and assistance.

Don’t pay ransom – There’s no guarantee you’ll get encryption keys after paying. It encourages more criminal activity.
Restore from backups – Your best bet for retrieving encrypted files is from backups made prior to infection.
Reset passwords – Change credentials for email, banking, and other sensitive accounts in case they were compromised.

Clean the infection – Use antivirus tools to scan and remove infected files. Reinstall operating system if needed.
Enable security tools – Learn from the attack and enable endpoint protection, email filtering, backups, etc.

Should you pay the ransom?

Security experts strongly advise against paying the ransom for several reasons:

No guarantee you’ll get decryption keys after paying. Criminals often pocket the money anyway.
Paying encourages and funds more ransomware attacks in the future.
There are often alternative ways to recover encrypted files without paying, like from backups.

Ransom amount could increase if they know you are willing to pay.
Money goes towards criminal enterprises often involved in other illicit activities.

A better approach is to use backups to restore your files and strengthen security to prevent future attacks. If facing substantial loss, you may consult data recovery firms, but expect high costs with low probability of success.

How to protect against ransomware

Use these security practices to guard against ransomware threats:

Maintain offline backups – Keep recent backups of important files on disconnected external drives.
Be wary of emails – Don’t open attachments or click links from unknown senders.

Exercise caution web browsing – Stick to trusted sites and avoid downloading files from suspicious ones.
Install security software – Use endpoint protection with behavior monitoring to detect ransomware.
Patch apps/OS – Keep your operating system, software, and apps updated with the latest patches.

Disable macros – If using Microsoft Office, disable macros to prevent infection through documents.
Use caution with USB drives – Scan removable media for malware before opening files.
Restrict file/folder access – Limit write access to shared folders and network drives.

Educate employees – Train staff to identify security threats through examples and simulations.

What does a CryptoLocker ransom note contain?

CryptoLocker ransom notes typically include:

A title indicating files are encrypted, often with the attackers’ name or logo.

Threats about deleting decryption keys if payment isn’t received.
Demands for payment in cryptocurrency like Bitcoin.
Instructions for making payment to the attackers’ Bitcoin wallet.

Deadline for payment, such as 72 or 100 hours.
Amount for ransom payment, usually $500 – $1000.
Contact info for making payment like email addresses.

Claims that files will be decrypted upon confirmed payment.

The note aims to compel victims to quickly pay the ransom. But as advised earlier, there are better ways to recover encrypted files than funding criminal enterprises.

What types of files does CryptoLocker encrypt?

CryptoLocker encrypts hundreds of different file types on local, network, and removable drives. Commonly targeted files include:

Documents – Word, Excel, PowerPoint files
Images – JPG, PNG, GIF, TIFF, RAW photos
Videos – AVI, WMV, MOV, MP4 files

Audio – MP3, WAV music and speech files
Archives – ZIP, RAR compressed containers
Email – PST, DBX, EML data files

Databases – SQL database files
Design – CAD, 3ds MAX, Sketchup drawings
Bookkeeping – QuickBooks, Sage accounting data

The goal is to encrypt any valuable, irreplaceable files to coerce victims into paying for decryption. Virtually any file type can be targeted.

How to prevent CryptoLocker and ransomware

These tips can help defend against CryptoLocker and other ransomware threats:

Install a reputable antivirus suite with behavior-based detection to block and remove ransomware.

Back up important files regularly on disconnected drives to enable restoration if encrypted.
Avoid opening attachments from unknown senders in email or instant messaging apps.
Exercise caution when downloading files and programs from the internet.

Keep software and apps updated with the latest patches and upgrades.
Disable browser plugins like Adobe Flash, Shockwave, QuickTime if not required.
Install pop-up blockers and ad blockers to avoid malicious ads.

Be wary of shortened URLs in emails and social media posts.
Scan external USB drives before opening any files.
Educate employees on ransomware prevention through examples of threats.

Following strong security practices minimizes your ransomware risk exposure.

Can antivirus stop CryptoLocker?

Mainstream antivirus programs have difficulty blocking newer strains of ransomware like CryptoLocker. However, advanced antivirus suites may detect and thwart CryptoLocker infections using:

Signature-based detection – Identifies known CryptoLocker variants based on code signatures.

Heuristics – Analyzes behavior of unknown code and scores level of suspicious activity.
Machine learning – Models help recognize new ransomware strains using AI algorithms.
Behavior monitoring – Watches for suspicious system changes like file encryption.

Exploit mitigation – Prevents malware from leveraging vulnerabilities to infect systems.

The most effective approach uses a blend of these techniques to detect both known and never-before-seen ransomware. Leading antivirus engines from vendors like BitDefender, Kaspersky, ESET, etc. can successfully block CryptoLocker in many cases.

Should you report ransomware to the authorities?

If victimized by ransomware, you should report it to law enforcement. Here’s why:

Aids investigation – Provides details that could reveal threat actors.
Warns others – Alerting authorities can warn other potential targets.
Strengthens cases – Accumulated reports build evidence against perpetrators.

Recovery assistance – Authorities may share decryptors or help recover some files.
Justice served – Reporting brings criminals to account which deters future crimes.
Disrupts payments – Authorities can sometimes disrupt ransom payments to curb funding.

Victim support – Agencies can recommend response steps and provide victim support.

By reporting ransomware incidents, you are helping strengthen cybercrime deterrence and investigation. US victims can contact the FBI or Secret Service while UK victims can inform Action Fraud.

What damage can CryptoLocker do?

CryptoLocker can inflict substantial damage to individuals and businesses by:

Encrypting files – Personal documents, photos, projects, databases, and system files end up encrypted and inaccessible.
Disrupting operations – Business processes dependent on access to files and systems are halted.
Generating losses – Work hours spent recovering files and productivity declines translated into monetary loss.

Damaging equipment – Attempting file recovery could damage storage media like hard drives.
Causing reputational harm – Customers lose confidence in businesses perceived as insecure.
Extorting ransom – Criminals extort funds through ransom demands, indirectly funding more crime.

Indirect damage like operational disruption and reputational harm can sometimes far exceed direct data loss and ransom payments.

CryptoLocker decryption without paying ransom

It may be possible to decrypt your files without meeting ransom demands using these methods:

Restore from backups – Use file backups made prior to infection to recover encrypted data.

Shadow volume copies – Some files may be recovered from shadow copies made before encryption.
Decryption tools – For some ransomware families, decryptors are released to help victims recover files.
Flaws in encryption – Weak implementation may allow decrypted certain file types like databases.

Brute forcing keys – With weak keys, it’s sometimes possible to crack encryption, but difficult.
File recovery – Recovery software can reconstruct portions of corrupted encrypted files.
Format and reinstall – As a last resort, reformat the drive and reinstall data from scratch.

Having a good backup is by far the most reliable method of recovering your data after a CryptoLocker infection. Other techniques may provide partial recovery, but often with considerable effort and costs.

Table: Summary of CryptoLocker defenses

Defense	Description
Backups	Maintain offline backups to restore encrypted files
Antivirus	Install advanced antivirus to detect and block ransomware
Caution	Avoid opening suspicious emails, links, attachments
Network security	Firewalls, email filtering, and network segmentation helps block threats
Access controls	Limit write access to folders like network shares to prevent encryption
Patching	Keep software updated to prevent exploits that deliver ransomware
Education	Train staff on ransomware response and prevention best practices

Conclusion

Ransomware like CryptoLocker is a persistent cyber threat that all individuals and organizations should take steps to protect against. The most effective approach combines security technology, vigilant practices, backups, and education to minimize the risk and business impact. With strong defenses in place, you can rest assured your data remains safe in the event of an attack.