Recovering From Ransomware and Crypto Viruses – Wimgo

Recovering From Ransomware and Crypto Viruses

Ransomware is one of the biggest cybersecurity threats facing businesses today. These malicious programs encrypt files on infected systems and demand payment in cryptocurrency to decrypt them. Victims that fail to maintain adequate backups can be forced to pay the ransom or face losing their data. 

Recent years have seen dramatic increases in ransomware attacks, with strains like Ryuk, Conti, Black Basta, Hive, LockBit, and others extorting hundreds of millions of dollars from affected organizations. High profile incidents have impacted employers like Garmin, Colonial Pipeline, JBS Meats, and thousands more.

This comprehensive guide will provide readers with detailed advice on protecting against, detecting, and responding to ransomware and crypto viruses. It will cover prevention best practices, building an effective response plan, leveraging backups and cyber insurance, and recovering disrupted systems.  

Understanding the ransomware threat landscape is critical for security leaders, IT teams, and employees at organizations of all sizes. By learning how these attacks occur and implementing safeguards like the ones outlined here, companies can minimize both the frequency and impact of ransomware incidents.  

What is Ransomware and How Does it Work?

Ransomware is a form of malicious software, or malware, that encrypts files on infected systems and extorts victims to pay a ransom to restore access. Ransomware programs make money by forcing users to pay cryptocurrency, usually Bitcoin, in exchange for a decryption key. Most ransomware strains give victims a short window to pay, sometimes 72 hours, before the ransom price increases or files become permanently inaccessible.

The infection begins when a user downloads or opens a malicious email attachment, clicks a compromised link, or visits an infected website. Once activated, the ransomware locates and encrypts critical files like documents, images, databases, and other data. Encrypted files typically get a new extension added like .encrypted or .ransomed.

A ransom note appears explaining payment instructions for procuring the decryption software needed to unlock files. Ransomware both encrypts live data and may delete volume shadow copies, preventing restores from Windows backups. Attacks may also disable antivirus tools and security controls to avoid detection.

Payment is no guarantee of recovering files. Some ransomware operators do not provide working decryption keys even after payment. Businesses that rely on paying the ransom can face repeated attacks. For these reasons, security experts strongly recommend against paying ransoms.

Common Types of Ransomware

Dozens of ransomware strains exist, with new variants continually emerging. Some current common ransomware types include:

– Ryuk: Targets large enterprises and encrypts network resources to cause maximum disruption. Infamous for the ransomware attack on Universal Health Services hospitals in 2020.

– Conti: One of most prolific ransomware groups in recent years hitting over 400 organizations. Conducts double extortion by threatening to leak data.

– Black Basta: Newer ransomware group that hit over 50 companies in several months during 2022. Uses triple extortion tactics.

– Hive: Targets organizations across multiple industries and countries. Unleashed over 1,300 attacks and extracted $100 million in ransom payments in 2021.

– LockBit: Prolific ransomware strain and ransomware-as-a-service offering. Breached 60 companies in the U.S. and Europe in just first half of 2022. 

– Clop: Focuses on technology sector targets. Extracted over $500 million in ransom payments from victims.

– REvil: Major ransomware group responsible for the attack on meat supplier JBS Foods in 2021 before disappearing. Re-emerged under new management in 2022. 

– Maze: Historic ransomware operation known for popularizing the double extortion tactic of threatening to leak stolen data.

How Ransomware Spreads 

Ransomware uses various vectors to infiltrate networks and endpoints:

– Phishing Emails: Malicious emails with infected attachments or links to compromised sites are the primary ransomware delivery method. Social engineering tricks users into enabling the infection.

– Software Vulnerabilities: Unpatched apps and operating systems offer ransomware an entry point. Exploits like EternalBlue and ProxyShell have enabled infections.

– Stolen Credentials: Brute forcing and credential stuffing attacks let ransomware use compromised logins to spread. Multi-factor authentication can mitigate this.

– Compromised Websites: Infected websites and malicious ads redirect to sites that deliver ransomware exploits known as drive-by downloads.

– Remote Desktop Protocol (RDP): Exposed RDP endpoints allow ransomware gangs to brute force their way into networks.

– Third Party Compromise: By compromising managed service providers, ransomware groups can simultaneously infect multiple downstream customers.

Preventing Ransomware Infections 

Completely preventing ransomware is difficult, but organizations can take steps to minimize risks:

– Email Security: Filter malicious attachments, links, and spam to stop socially engineered ransomware. Block risky file types like .exe and .js at the gateway.

– Vulnerability Management: Patch operating systems, software, and firmware consistently and rapidly. Prioritize fixes for known exploited vulnerabilities.

– Multi-factor Authentication: Require strong MFA for all remote access like VPN and RDP to prevent brute forcing. 

– Least Privilege: Only provide users and accounts with minimal access required for their role to limit ransomware spread. 

– Network Segmentation: Use firewalls to isolate and segment parts of the network to obstruct ransomware movement.

– Endpoint Detection & Response: Deploy EDR tools on endpoints to detect ransomware execution early. Shut down infections before encryption starts.

– Web Filtering: Block access to known malicious sites and ads. Disable Flash and advertisements which deliver ransomware. 

– Employee Training: Educate staff to identify social engineering techniques and risky links. Conduct simulated phishing exercises.

Detecting a Ransomware Attack

Despite best efforts, ransomware may still infiltrate environments. Swiftly detecting an attack is crucial for minimizing damage. Warning signs of a ransomware incident include:

– Sudden inability to access files that produce errors indicating encryption.

– Renamed files appended with new extensions like .encrypted. 

– Ransom notes appearing on screens demanding cryptocurrency payment.

– Increased activity by data recovery and backup tools trying to access changed files. 

– Crashed systems, services, and apps due to ransomware terminating processes.

– Antivirus alerts for ransomware or unknown malicious programs executing.

– Signs of data exfiltration to external sites anticipating extortion.  

– Strange SMTP traffic from internal systems sending malware to other endpoints.

– Spikes in CPU, network bandwidth, or disk activity from ransomware encrypting data.

Once ransomware is identified, immediately isolate infected systems to halt propagation. Analyze antivirus reports or malware samples to determine the ransomware strain if possible.

Responding to a Ransomware Attack 

Recovering from a ransomware incident requires methodical steps and coordination. Do not allow employees to continue using infected computers. The response should include:

Isolate the Infection

– Disconnect ransomware-stricken systems from the network immediately to prevent lateral spread. Disable Wi-Fi and unplug Ethernet cables.

– Shut down remote access like VPNs and require staff to work from uninfected systems.

– Block email attachments and scan all incoming email to avoid reinfection.

– Isolate backups and ensure they remain malware-free so recovery is possible.

Determine the Strain 

– Identify known signatures, behaviors, and patterns to pinpoint the ransomware variant. ryuk, CloP, Conti, etc.

– Submit malware samples to security researchers and law enforcement to support identification.

– Review antivirus scans and behavior reports to understand scope and transmission methods.

Do Not Pay the Ransom

– Paying the ransom encourages and funds criminal ransomware groups. There is also no guarantee files will be recovered.

– If payment is made, threat actors may leak this information to other groups who will repeatedly attack.

– Payment can violate regulations prohibiting financing criminal organizations.

Restore from Backups  

– Recent, unaffected backups are critical for restoring encrypted data without paying ransom. Test backups to ensure recoverability.

– Incremental and differential backups may preserve malware, so restore the last clean full backup before infection.

– Rebuild system from the ground up if backups are inadequate or to eradicate dormant infections.

Rebuild Systems When Needed

– Completely rebuild infected systems using trustworthy operating system install media.

– Only restore data from known good backups once the system is cleaned.

– Change all passwords after rebuilding systems to prevent reinfection via persistence mechanisms.

Using Antivirus and Anti-Ransomware Software

Modern antivirus (AV), endpoint detection and response (EDR), and anti-ransomware tools can block and limit many ransomware infections. Consider solutions that provide:

– Behavior-based detection – Analyzes processes and patterns to identify ransomware actions like file encryption.

– Block at first sight – Stops never before seen ransomware variants based on behavior rather than known signatures. 

– Rollback – Reverses file changes made by ransomware during the attack.

– Immutable backups – Makes backups unchangeable by ransomware encryption.

– Vaccination – Makes files and folders unable to be encrypted by locking them down at the file system level.

Keep all AV and anti-ransomware tools up-to-date and fine-tune detection settings for your environment. Admins should centrally manage security tools to prevent tampering by ransomware that disables some defenses.

Employing the 3-2-1 Backup Rule 

Maintaining robust, segmented, and secure backups is paramount for ransomware resilience. Consider the 3-2-1 backup rule:

– 3 copies of data – Retain backups in three separate locations like local, NAS and cloud storage.

– 2 types of media – Store backups on two different media types such as HDDs and tape to mitigate disaster risks.

– 1 copy offsite – Keep at least one backup copy physically offsite or at a disaster recovery location.

Also, carefully control access to backups, encrypting data at rest and in transit. Use immutable or append-only backups that restrict alteration or deletion by ransomware. Regularly test restores to validate recovery processes.

Rotate full and incremental backups following the Grandfather-Father-Son scheme, retaining multiple generations but prioritizing most recent data. Determine required backup frequency and retention duration based on tolerance for data loss.

Understanding Cyber Insurance 

Cyber insurance can offset some costs of ransomware incidents, including:

– Ransom payments (typically negotiated down)

– Investigation, remediation and restoration expenses  

– Legal services, fines and lawsuit damages

– Public relations services

– Lost business income during disruptions

However policies vary greatly in coverage. Carefully evaluate options and limits for ransomware-related claims. Maximize coverage for first and third party losses. 

Consider insurers with experience handling ransomware incidents. Ask about policy exclusions and rider options that expand protection. Increase coverage as your organization’s exposure grows.

Following Best Security Practices

Building robust ransomware defenses requires following security best practices in key areas:

Patch Management – Prioritize patching critical OS and software vulnerabilities exploited by ransomware. Rapidly deploy updates using automation.

Access Controls – Limit user privileges and restrict account access including third parties. Disable inactive accounts. 

Advanced Email Security – Scan all email attachments for malware. Block dangerous file types and filter suspicious senders.

Web Security – Limit web browsing to trusted sites only. Block ads and enforce application allow lists on endpoints. Disable Flash.

Network Segmentation – Use firewalls to control and restrict lateral movement between network zones and across endpoints.  

Vulnerability Assessments – Continuously scan internal and external networks for risks and misconfigurations that may enable ransomware spread. Remediate all critical findings.

Penetration Testing – Conduct controlled attacks against your environment to identify vulnerabilities and insecure practices before criminals do.

Creating a Ransomware Response Plan

Every organization should develop and document an incident response plan for ransomware attacks that includes:

– Defined roles and responsibilities during the response. Who makes decisions? Who gets notified and when? Who talks to law enforcement?

– Step-by-step procedures for containing, investigating and remediating infections on servers and endpoints. 

– Plans for public relations, legal services and communicating with customers after an attack.

– Methods for assessing damage and loss severity following an incident.

– Procedures for restoring data from known good backups once systems are rebuilt and malware is eradicated.  

– Controls over data held for ransom to avoid adding regulatory violations to an incident. 

Train staff on plan activation procedures and their individual response roles. Conduct ransomware response exercises to validate effectiveness and identify gaps. Update the plan regularly as new threats emerge.

Leveraging Threat Intelligence 

Threat intelligence provides insights into ransomware adversary tactics, techniques and procedures (TTPs). Stay updated on emerging strains, exploits, and adversary groups by:

– Monitoring threat intelligence feeds and reports from vendors and government entities (CISA, MS-ISAC, etc).

– Participating in Information Sharing and Analysis Organizations (ISAOs) and Computer Emergency Response Teams (CERTs) to collaborate with peers. 

– Following ransomware support sites like NoMoreRansom.org which provide decryptors and advice for many strains.

Use threat intel to improve defenses against known ransomware behaviors. For example, monitoring underground forums may provide early warnings about upcoming ransomware campaigns.

Educating Employees on Ransomware Risks

While technology provides critical defenses, employees present a key attack vector through social engineering. Robust security awareness training is essential and should cover:

– How ransomware infects systems and spreads within organizations.

– Phishing techniques used to deliver ransomware like malicious attachments and links. 

– Critical thinking for identifying unusual system behavior that may indicate infection.

– Reporting suspicious activity like ransom notes or file access errors to IT security teams.

– Safeguards like not opening unsolicited attachments, using strong passphrases, and enabling multi-factor authentication.  

Test staff knowledge using simulated phishing exercises. Reinforce learning with regular refreshers on latest threats and response procedures. Everyone has a role to play in stopping ransomware.

Summary and Conclusion

Ransomware remains a severe threat to organizations globally. However, by taking proactive measures to prevent, detect, contain and respond to incidents organizations can minimize disruptions and recover more quickly. Leveraging backups, network segmentation, endpoint security, and user education provides layered defenses against infection. 

No solution will fully guarantee immunity from ransomware. But organizations willing to invest in best practices can greatly reduce risks and build resilience against different attack types. Keeping plans and tools up-to-date as threats evolve is essential.

While some infections may still occur, proper preparation and response can help companies weather ransomware storms. Don’t become another victim. Take action today to secure your environment against ransomware and data extortion.