Ransomware is malware that encrypts files on a device. The files and the systems that rely on them become unusable. A demand for payment usually follows. Many attacks start with phishing, and attackers may also threaten to leak stolen data. This guide explains the main ransomware types, how an attack unfolds, and how to defend against it.
Ransomware remains a rapidly changing threat in the global cybersecurity landscape, even in 2025. Despite massive investments in digital security tools and heightened awareness across corporate and public sectors, ransomware attacks persist with alarming frequency and impact. One key reason for this is ransomware tactics’ ever-changing nature. Attackers no longer rely solely on simple phishing schemes. Instead, they now employ highly advanced methods such as double extortion, fileless infections, and using zero-day vulnerabilities to bypass even advanced security systems. These changing techniques make attacks harder to detect and harder to contain once they start.
What Is A Ransomware Attack?
A ransomware attack is a type of cybercrime. Attackers secretly infiltrate a computer system or network. They then encrypt key files or lock users out of their devices. After this, they demand a ransom, usually in cryptocurrency, to provide a decryption key or restore access. This makes the victim’s data or system unusable until the ransom is paid.
These attacks have become widespread because they are profitable for criminals and often catch victims unprepared. Often, ransomware enters a system through common methods such as:
- Phishing emails: Fraudulent emails trick users into clicking malicious links or opening infected attachments.
- Malicious downloads: Drive-by downloads happen when users visit compromised websites that automatically download malware.
- Exploiting software vulnerabilities: Attackers take advantage of outdated or unpatched software to gain access.
Once inside, the ransomware quickly encrypts files or locks the system. It then displays a ransom note that explains how to pay. The note threatens permanent data loss or public exposure if the demand is not met.
Because ransomware attacks can disrupt key services, halt business operations, and cause severe financial and reputational damage, understanding how they work is crucial. Early detection and prevention are key to minimizing harm.
What Are Ransomware Types?
Ransomware is not a single, uniform threat—it comes in many forms, each with its own attack methods and impact. Understanding the different types of ransomware helps companies and people recognize, respond to, and prevent these attacks better. Here are the most common and new ransomware types as of 2025:
1. Crypto Ransomware (Encryption Ransomware)
This is the most widespread type. Crypto ransomware encrypts files, folders, or entire drives, making data inaccessible. Victims receive a ransom note demanding payment in exchange for the decryption key.
Examples: WannaCry, CryptoLocker, Locky
2. Locker Ransomware
Locker ransomware locks users out of their devices or operating systems, preventing any access to files or apps. Unlike crypto ransomware, it does not encrypt files but blocks access to the entire system until the ransom is paid.
Examples: WinLocker, Police Trojan
3. Ransomware-as-a-Service (RaaS)
RaaS is a business model where cybercriminals rent out ready-made ransomware kits to affiliates, who then launch attacks. The creators take a share of the ransom. This model has lowered the barrier for entry, allowing less technical criminals to participate.
Examples: DarkSide, Sodinokibi (REvil)
4. Doxware (Leakware)
Doxware threatens to publish or leak sensitive personal or corporate data unless a ransom is paid. This “double extortion” tactic increases pressure on victims, especially companies with confidential data.
5. Scareware
Scareware uses fake alerts, pop-ups, or warnings to scare users into believing their device is infected or compromised. It pressures victims to pay for unnecessary “clean-up” tools or services. While less destructive, it can still cause financial loss and anxiety.
Examples: Fake antivirus software, rogue security programs
Why does this matter?
Each ransomware type requires different detection and defense plans. For example, while routine backups can help recover from crypto ransomware, doxware, and locker ransomware. They demand more measures such as data leak prevention, network segmentation, and strong access controls.
| Topic | Crypto | Locker | Doxware |
|---|---|---|---|
| What it does | Encrypts files, folders or drives | Locks users out of the device or system | Threatens to publish or leak sensitive data |
| What the victim is told | Pay for the decryption key | Pay to restore access | Pay or the data is leaked |
How Does the Ransomware Attack Lifecycle Work, with a Focus on Phishing?
A ransomware attack often follows a multi-stage lifecycle. Understanding each step helps companies spot warning signs early and use strong defenses, especially against phishing, which is often the attack’s starting point.
- Initial accessPhishing emails with malicious attachments or linksTechnique T1566 (MITRE ATT&CK, opens in a new tab)
- Persistence and privilege escalationBackdoors, stolen credentials, unpatched flaws
- Payload deployment and lateral movementSpread to shares, servers and backups
- Encryption and extortionFiles encrypted, ransom note shownTechnique T1486 (MITRE ATT&CK, opens in a new tab)
- Impact and recoveryDepends on backups, incident response and negotiation
1. Initial Access: Phishing as the Entry Point
Many ransomware attacks begin with a phishing campaign. Attackers craft convincing emails that appear to come from trusted sources, such as colleagues, partners, or popular services. These emails may:
- Contain malicious attachments (e.g., fake invoices, resumes, or reports)
- Include links to compromised websites or fake login pages
- Use urgent language to trick users into acting quickly
When a user clicks the link or opens the attachment, malware is silently downloaded onto their device. This gives the attacker a foothold in the network.
Technical Note: Advanced phishing emails may bypass basic spam filters. They can use personalized details (spear phishing) or previously leaked credentials. They can also exploit zero-day vulnerabilities in email clients or browsers.
2. Establishing Persistence and Privilege Escalation
Once inside, the ransomware attempts to keep access and escalate privileges. This can involve:
- Installing backdoors or remote access tools
- Harvesting credentials to move laterally within the network
- Exploiting unpatched vulnerabilities to gain admin rights
3. Payload Deployment and Lateral Movement
The attacker then deploys the ransomware payload, which may:
- Encrypt files on the local machine
- Spread to network shares, servers, and backups
- Disable security tools to avoid detection
Fileless ransomware may use real tools like PowerShell or Windows Management Instrumentation (WMI) to avoid leaving traces.
4. Encryption and Extortion
The ransomware encrypts key files and displays a ransom note, often demanding payment in cryptocurrency. In double extortion attacks, attackers may also threaten to leak stolen data if the ransom isn’t paid.
5. Impact and Recovery
Victims lose access to key data and systems, disrupting business operations. Recovery depends on backup availability, incident response readiness, and negotiation outcomes. Our free ransomware response playbook and checklist gives you a plan to fill in before it happens.
Why Phishing Matters in the Ransomware Lifecycle
- Phishing is one of the common initial access vectors for ransomware.
- Attackers exploit human error, bypassing even strong technical defenses.
- Advanced phishing campaigns use social engineering, brand impersonation, and even compromised real accounts.
How Can You Defend Against Phishing-Driven Ransomware Attacks?
Technical Controls:
- Advanced email security gateways with real-time threat intelligence
- Attachment and URL sandboxing
- Multi-factor authentication (MFA) for email and remote access
- Endpoint detection and response (EDR) tools
User Awareness:
- Routine phishing simulation exercises
- Training on recognizing suspicious emails, links, and attachments
- Clear reporting channels for suspected phishing attempts
Brandefense Approach: Proactive Phishing Defense and Automated Takedown
Phishing is one of the most common entry points for ransomware. Brandefense offers a proactive, multi-layered defense plan against it. The plan combines advanced detection, ongoing monitoring, threat intelligence, and automated takedown features.
Ongoing and Full Phishing Detection
Brandefense operates 24/7, always scanning the digital landscape for any and all potential phishing threats targeting your company. Our advanced detection engines study domains, websites, social media content, and more to find both confirmed and potential phishing incidents.
- Confirmed Phishing: Our systems may determine with certainty that a website, email, or social media post is malicious and built for phishing. When that happens, we right away notify our customers with clear, actionable intelligence.
- Potential Phishing: If a threat is found as a potential (but not yet confirmed) phishing attempt, Brandefense places it under ongoing observation. We monitor for any changes in content, behavior, or indicators. If the threat escalates and meets our criteria for confirmed phishing, we promptly update its status and alert the customer without delay.
Automated Takedown and Transparent Process Tracking
Brandefense empowers customers with an automated takedown request system. Customers can initiate takedown procedures for confirmed phishing sites or malicious content. Our platform provides:
- Expert support throughout the process. Customers know exactly what to do in case of delays or denials, and support helps speed up resolution when needed.
Integrated Threat Intelligence and Attack Surface Monitoring
Brandefense’s approach is further strengthened by strong threat intelligence and attack surface monitoring:
- Threat Intelligence: We deliver real-time feeds and in-depth analysis of new phishing campaigns, ransomware trends, and attacker tactics. This intelligence enables organizations to expect threats and adapt their defenses proactively.
- Attack Surface Monitoring: Brandefense finds exposed credentials, misconfigured services, and leaked data that could be exploited in phishing or ransomware attacks. This helps companies close vulnerabilities before they can be abused.
Brandefense delivers an end-to-end solution for phishing-driven ransomware threats: from early detection and ongoing monitoring to automated takedown and actionable threat intelligence. Our transparent processes and expert support ensure that companies can respond rapidly and well, minimizing risk and protecting digital assets and reputation.
What Are the Ransomware Trends and Predictions for the Future?
Q1 2025 Highlights from Brandefense
Ransomware remains a dynamic threat. Brandefense’s Q1 2025 report, studying 1,038 incidents across 62 countries and 38 active groups, reveals key shifts:
- Dominant Actors: RansomHub led with 22.3% of attacks, followed by rapidly growing groups like Lynx (entering the Top 10), Cactus, Play, and Incransom. The “Others” category (23.6%) shows persistent smaller group activity, fueled by RaaS models.
- Top Targets: Manufacturing (20.5%) continued to be the most attacked sector, with business services, construction, and retail also heavily impacted.
- Geographic Focus: The U.S. (61.3%), Canada, and the UK remained primary targets, with North America accounting for 69% of global incidents.
- Changing Tactics: Attackers increasingly exploited supply chain weaknesses, third-party services, and exposed remote access points. Double extortion remained prevalent, intensifying pressure on victims.
Predictions for H2 2025
Based on these trends, Brandefense predicts the following for the remainder of 2025:
1. Rise of Niche Groups: Expect increased activity from smaller, agile ransomware groups targeting less-defended sectors.
2. Broader Geographic Focus: While North America remains a primary target, groups will intensify attacks in EMEA and APAC.
3. Advanced Phishing: Phishing will remain the top entry point, changing with more advanced social engineering and multi-channel attacks.
4. AI & Automation in Attacks: Attackers will increasingly use AI for faster reconnaissance, stronger evasion, and automated operations.
5. Triple Extortion Shift: Beyond data encryption and leaks, expect more direct threats to the victim’s customers or partners for increased pressure.
6. Supply Chain Exploitation: Critical infrastructure and supply chains will face even more targeted and disruptive attacks.