Ransomware is a type of malicious software that blocks access to a computer system or data until a ransom is paid. It has become a lucrative criminal enterprise, with estimates of ransom payments totaling over $1 billion in 2016 alone. Ransomware does not just target home users – businesses and government agencies have also been impacted. Understanding how ransomware gets on computers in the first place is key to avoiding infection.
How is ransomware distributed?
There are several common methods that cybercriminals use to distribute ransomware. These include:
- Email phishing attacks: Malicious email attachments or links can install ransomware when opened. Criminals masquerade as a legitimate company or person to trick the recipient.
- Infected websites: Visiting compromised websites can trigger a ransomware download, especially if plugins like Flash or Java are outdated. This is known as a drive-by download attack.
- Remote Desktop Protocol (RDP) compromises: Brute force hacking of RDP can allow criminals access to install ransomware remotely on a network.
- Software vulnerabilities: Exploits targeting vulnerabilities in operating systems, applications, and network devices can distribute ransomware.
- Malvertising: Malicious ads on websites can install ransomware if clicked on.
In addition, compromised legitimate programs like installers and software cracks can be Trojanized to distribute ransomware to unsuspecting users. Pirated software in particular is a common infection vector. Cybercriminals are very opportunistic and take advantage of any vulnerability they can find.
What are the typical phishing attack methods?
Phishing attacks aimed at spreading ransomware often take the following forms:
- Malicious attachments: Files like zipped documents or PDFs prompt users to click and enable macros or content. Instead they install malware.
- Malicious links: Embedded URLs in emails redirect to ransomware download sites when clicked.
- Spear phishing: Highly customized emails target specific individuals or companies to appear more legitimate.
- Business Email Compromise (BEC): Attacker spoofs executive email accounts to trick employees into payments.
- Pop-up ads: Malicious ads mimicking system warnings or software offers install ransomware if engaged.
Social engineering is heavily used to create urgency or panic that causes victims to bypass security policies and install malicious software inadvertently.
What website vulnerabilities may lead to ransomware?
Poorly secured websites can provide an opening for ransomware infection through:
- Outdated Content Management Systems (CMS): WordPress, Joomla etc. with unpatched vulnerabilities allow exploit kits to be installed.
- Vulnerable Web Plugins: Weakly secured plugins like Java and Flash enable ransomware downloads if they have not been updated.
- SQL injection attacks: Attackers inject malicious SQL code into entry fields of websites to access backend data and systems.
- Cross Site Scripting (XSS): Javascript malware can be installed into websites through code injection in input fields.
- Zero-day exploits: Unknown vulnerabilities are rapidly exploited before patches become available.
Any website that stores private user information without adequate security could expose visitors to drive-by ransomware installation.
How do RDP compromises distribute ransomware?
Remote Desktop Protocol (RDP) provides remote administrative access to computing systems. Unfortunately, criminals exploit weak RDP security to infiltrate networks and install ransomware. Typical avenues include:
- Brute force attacks: Automated programs guess weak usernames and passwords until they gain entry.
- Stolen credentials: RDP access credentials are stolen from other breaches and re-used by attackers.
- RDP port forwarding: RDP TCP port 3389 forwarded through firewalls exposes systems to the public internet.
- Unsecured cloud instances: Cloud-based virtual desktops like AWS Workspaces with public exposure and weak passwords.
Once inside the network, attackers can disable security software, steal credentials, and deploy ransomware across any connected systems. RDP hygiene such as multi-factor authentication, lockout policies, and avoiding public exposure are vital to protect against hands-on ransomware installation.
What software vulnerabilities raise the risk of ransomware?
Cybercriminals are constantly searching for new vulnerabilities in common software products. Major exploits include:
- Unpatched operating systems: Dormant vulnerabilities in OS like Windows or Linux allow escalated access to deploy ransomware once exploited.
- Vulnerable network devices: Unpatched routers, VPNs, firewalls, and switches provide entry points into company networks.
- Unpatched browsers and plugins: Web browsers like Chrome, Firefox, IE, and Edge have frequent zero-day exploits that can install drive-by ransomware.
- Out-of-date Java & Adobe: These popular applications have dedicated teams of hackers searching for weaknesses.
- Microsoft Office macros: VBA macros in Office documents provide an easy infection mechanism requiring minimal user interaction.
Prompt patching, secure configurations, and isolation of sensitive systems can help mitigate ransomware installation through unpatched vulnerabilities.
What techniques does malvertising use to spread ransomware?
Malvertising refers to malicious advertisements used as vessels for ransomware infection. Typical techniques include:
- Malware payloads: Flash, Javascript, or iFrame code that triggers downloads or exploitation.
- Social engineering ads: Mimic system errors to get users to install fake malware cleaning programs.
- Targeted ads: Display malicious ads only to select geographic regions or demographics.
- Timing randomization: Malware only triggers for a small percentage of impressions to avoid detection.
- Domain rotation: Continually rotate malicious domains used to bypass blacklists.
These malvertisements infiltrate trusted websites through tainted ad networks desperate for revenue. Distinguishing legitimate vs. fake ads can be extremely difficult.
How does pirated software facilitate ransomware?
Pirated or cracked software circumvents licenses and copyright using hacked installation files. These Trojanized programs act as unchecked vectors to distribute ransomware including:
- Infected game mods: Custom game add-ons contain malware payloads that extract during installation.
- Hacked games and software: Modified .exe or installer files contain embedded malware insertion tools.
- Key generator exploits: Fake keygen tools claim to unlock paid software but actually install ransomware.
- Torrent poisoning: Malware payloads are uploaded to file-sharing torrents under guise of legitimate pirated data.
- Steam game hacks: Cheat hacks for Steam games spread ransomware and login credential stealing malware.
The promises of free unlocked software or bonus cheats are difficult for many users to resist. But pirated programs come from untrusted sources and provide an easy infection route for ransomware criminals.
How can email phishing attacks be identified?
These warning signs can help identify a potential ransomware phishing email:
- Generic greetings – Addresses like “Dear user” instead of your name.
- Spoofed sender – Check email address is from legitimate domain.
- Sense of urgency – Language creating unrealistic deadlines and pressure.
- Threats – Stating accounts or services will be closed.
- Curiosity – Subject lines inducing strong curiosity to open.
- Mismatched links – Displayed URL doesn’t match actual destination.
- Unexpected attachments – Unexplained files from trusted contacts.
Scrutinizing the sender, content, links, attachments, and writing style can reveal many indicators of a phishing email scam.
What processes run ransomware and encryption?
Once delivered to a victim machine, ransomware uses these technical processes to take effect:
- Environment setup – Disables recovery tools, antivirus, Windows updates etc.
- Map networks – Enumerate connected computers, file shares, and other targets.
- Generate keys – Create public-private keypair for RSA encryption algorithm.
- Scan files – Recursively search for data to encrypt across all directory levels.
- Encrypt files – Encode target files using cryptography with attacker’s public key.
- Delete originals – Remove non-encrypted versions of files after encryption.
- Ransom note – Display payment instructions for decrypting files.
Powerful ransomware like Ryuk can encrypt hundreds of gigabytes in minutes. Payloads are encrypted with virtually unbreakable algorithms without the attacker’s private key.
What network protocols help ransomware spread?
These network protocols enable ransomware to traverse computers in a network:
- SMB – Server Message Block for Windows network file shares.
- RPC – Remote Procedure Call enables command execution on remote hosts.
- SSH – Remote shell access Allows ransomware to spread to Linux/Unix.
- VPN – Virtual Private Network gives access to devices on home and public networks.
- RDP – Remote Desktop Protocol enables direct control of Windows machines.
- Tor – The Onion Router anonymizes traffic and connections.
Once an initial foothold is established, ransomware uses built-in connectivity of modern networks to fan out across as many machines as possible. Internal firewalls should block unnecessary protocols to limit lateral movement.
How does ransomware attempt persistence on systems?
To remain on systems undetected, ransomware uses techniques like:
- Registry modifcations – Adds executable startup values in registry hives like RUN and AppInit_DLLs.
- Service exploits – Install as malicious service started on boot.
- DLL preloading – Name ransomware DLLs to be loaded by legitimate processes.
- Schtask exploits – Creates scheduled tasks to repeatedly execute itself.
- Startup folder – Saves executable in common Startup folder to launch each login.
- Cron jobs – Creates cron scripts to repeatedly run itself on Unix/Linux.
These persistence mechanisms make ransomware difficult to fully remove from infected systems. A clean rebuild is often required for recovery after infections.
What are the consequences of ransomware infections?
Beyond just encrypting files, ransomware can severely impact affected individuals and businesses through:
- Lost productivity – Systems become unusable for staff until fixed.
- Defacement – Homepages, databases etc. may be altered.
- Data theft – Unsecured files may be exfiltrated before encryption.
- Breach disclosure laws – Personal data leaks may require public reporting.
- Forensic costs – Extensive efforts required to conduct root cause analysis.
- Permanent data loss – Failures in backups result in non-recoverable information.
Paying the ransom is no guarantee files can be restored. Ransomware can cause damages stretching long after the initial infection.
What steps help recover from ransomware?
A systematic recovery process helps resume operations after ransomware. Critical steps include:
- Disconnect infected systems – Isolate to prevent continued spread.
- Secure backups – Ensure no backup contamination.
- Notify authorities – Engage law enforcement and cybersecurity agencies.
- Perform forensics – Determine root cause, variants, and vulnerabilities.
- Rebuild systems – Completely refresh infected computers.
- Enhance security – Update all software, patch vulnerabilities, refresh credentials.
- Restore data – Recover from verified clean backups.
Testing backups, improving defenses, and extensive monitoring of logs and networks aim to prevent repeat infections going forward.
How can individuals prevent ransomware infections?
All computer users should enact these measures to avoid ransomware:
- Update software – Patch operating systems, browsers, and applications.
- Use antivirus – Maintain active, updated protection.
- Avoid downloads – Never open unsolicited files or programs.
- Don’t click ads – Use adblockers to avoid malvertisements.
- Backup data – Maintain current backups offline.
- Watch out for phishing – Verify senders and never share info.
Following cybersecurity best practices minimizes the risk and impact of ransomware and malware infections for any user.
What enterprise defenses counter ransomware?
Businesses should layer these security controls to block ransomware:
- Email filtering – Block dangerous attachments, links, and senders.
- Web filtering – Restrict access to malicious sites.
- Firewall policies – Allow only necessary ports/protocols.
- IPS protection – Block exploits, anomalies, and signature attacks.
- Sandbox suspicious files – Safely test behavior before delivery.
- Staff education – Teach techniques to identify social engineering.
- Backup frequently – Enable quick recovery after infection.
Layered cybersecurity defenses provide overlapping protection to best avoid disruptive ransomware infiltrating organizational networks.
Conclusion
Ransomware has emerged as a dominant attack vector for cybercriminals seeking financial gain. Delivery mechanisms continue to evolve, making awareness and vigilance vital. By understanding how ransomware successfully targets vulnerable computers, individuals and businesses can enact controls and safe computing practices to minimize their risk of infection.
Keeping devices updated, securing networks, avoiding suspicious downloads, backing up data, and verifying emails are key universal protections against ransomware. Technical controls like firewalls and filters add additional layers of defense for organizations. However, cybercriminals show endless creativity in their social engineering and technical exploits. Continued education and research into ransomware tactics allows computer users to maintain an adaptive defensive posture against this prevalent threat.