What Is Ransomware Removal?

Ransomware has become one of the most dangerous threats to businesses in every industry, and ransomware removal is an essential step in protecting an organization and its network, data, and users. While ransomware prevention is the top priority for security teams, understanding strategies and tools for ransomware removal is equally important, since it’s impossible to successfully defend against every ransomware threat. When an organization falls prey to ransomware, the ability to quickly execute an incident response plan that includes ransomware removal can help to limit the damage caused by this type of malware.

Ransomware is a type of malicious software that cybercriminals use to encrypt files on a victim’s computer, mobile device, or network, making them inaccessible to users. This allows criminals to demand a ransom payment, typically in a cryptocurrency like bitcoin, in exchange for the decryption keys needed to restore access to files. Ransomware variants like LockBit ransomware, WannaCry, CryptoLocker, and Ryuk ransomware have caused significant disruption to businesses worldwide. Ransomware as a service (RaaS) offerings now allow threat actors with very little knowledge or experience to carry out devastating ransomware attacks, making it imperative that organizations and their security teams adopt solutions for ransomware prevention and ransomware removal.

Threat actors use a variety of techniques to infect networks and IT environments with ransomware. Phishing emails are a common tactic. These messages contain malicious links or attachments that, when clicked on or opened by a user, surreptitiously download malware to the victim’s network or device. Hackers may also gain access to networks by exploiting vulnerabilities in software or in operating systems, including Windows, Linux, and macOS. Additional attack vectors include social media scams, using credentials stolen during data breaches, social engineering tactics that dupe users into revealing account credentials, and Trojan malware that appears to be a legitimate application or software update.

Once ransomware is downloaded to a machine, it performs a series of actions. These may include modifying registry files and disabling security software to prevent the ransomware from being detected. Ransomware may also escalate privileges to gain access to other systems and accounts, and identify valuable data that could be targeted for encryption or theft. Some ransomware strains exfiltrate data to an external server, allowing attackers to threaten to leak or publish sensitive data unless a ransom is paid. Ultimately, ransomware encrypts files on a device or within a network, changing file extensions and leaving a ransom note on drives or in pop-up messages with instructions about how to make a ransom payment.

There are several steps involved in ransomware removal, remediation, file decryption, and data restoration.

• Detection. Early detection of ransomware is the most effective way to stop an attack and minimize damage. Anti-virus, anti-malware and anti-ransomware solutions can help security teams with early detection.

• Isolation. Once a ransomware infection is detected, IT teams must quickly move to isolate any affected systems from other machines and from Wi-Fi and wired networks. This prevents the malware from spreading to other sites and from communicating with the attacker’s command and control servers.

• Identification. After restarting a computer in safe mode to limit the ransomware’s ability to execute, security teams can use tools to identify the type of ransomware involved in an attack. This information is critical to attempts at ransomware removal and decryption.

• Communication. Reporting a ransomware attack to authorities helps security agencies to develop better real-time threat intelligence for ransomware and assists law enforcement agencies in taking down ransomware sites and criminal gangs.

• Ransomware removal. There are a variety of robust anti-ransomware solutions — including tools from Kaspersky, McAfee, and Trend Micro — that can help to identify and remove malicious files. Removal of all ransomware code is essential to preventing additional files and backup files from being infected.

• Decryption. There are ransomware decryption tools available for a broad range of ransomware. However, once a decryptor has been developed for a particular strain of ransomware, ransomware operators tend to alter their code to resist decryption. Consequently, it’s not always possible to decrypt files, and many sophisticated variants remain impervious to decryption efforts.

• Recovery. Once ransomware removal is complete, IT teams can restore files from a clean backup from external hard drives or cloud storage.

Security professionals and law enforcement agencies like the FBI discourage organizations from paying a ransom for several reasons.

• Even if a ransom is paid, there’s no guarantee that the cybercriminals behind the ransomware attack will provide a decryption key or honor their promise not to leak sensitive data.

• Some types of ransomware are unencryptable, even with a ransom payment.

• Paying a ransom only encourages cybercriminals to continue launching ransomware attacks.

Because organizations can’t always count on ransomware removal to completely restore their files, it’s critical that cybersecurity teams focus on ransomware protection and prevention. Best practices include:

• Back up data regularly. Backups should be encrypted, immutable, and offline, making it harder for ransomware to access and infect files in backup storage.

• Deploy multiple layers of security. Antivirus software monitors and blocks any traffic that shows signs of viruses, malware, and ransomware. Firewalls prevent unauthorized traffic between the network and the internet. Endpoint security solutions protect individual servers, PCs, mobile devices, and IoT devices. Intrusion detection systems (IDS) identify potential attacks by monitoring network traffic logs and alerting IT teams to potential malicious activity, and microsegmentation solutions prevent unauthorized lateral movement.

• Implement strong access control. Solutions like multifactor authentication, ZTNA, strong passwords, and least-privilege access help to ensure that only authorized users, devices, and applications can access IT environments, and that users have access only to the resources they need at any given moment.

• Filter email. Email filtering technology detects and blocks potential phishing attempts and other cyberattacks.

• Patch and update. Continually and regularly applying patches and updating systems helps to mitigate zero-day vulnerabilities in software and hardware that threat actors may exploit to gain access to IT environments.

• Train users. Security awareness training addresses the weakest link in the security chain — users and employees. Training helps users to spot phishing attacks and to develop security hygiene practices that can reduce the likelihood of a successful ransomware attack.