Comprehensive Measures Against Ransomware Attacks

Ransomware, a malicious software program, encrypts a victim’s data, hindering access until a ransom is paid. This threat can impact individuals and businesses alike, posing a significant risk for organizations managing vast amounts of data. Implementing a robust security strategy is vital to mitigate this threat. This guide outlines effective precautionary measures to protect your computer network from ransomware attacks.

Strengthening Network Defenses:

1. Restrict Network Access: Block specific ports (TCP/UDP 445, 137, 138, 139) on network perimeters and internal devices to deter unauthorized access. Utilize firewalls and host-based anti-malware solutions to further restrict access on individual devices.
2. Patch Management: Promptly install all security patches, particularly those addressing vulnerabilities mentioned in Microsoft Security Bulletin MS17-010, to keep operating systems and applications up-to-date.
3. Secure Email Systems: Deploy antivirus and anti-spam solutions on mail servers to filter out malicious emails containing malware attachments or phishing links.

User Awareness and Education:

1. User Alertness: Inform users about potential threats and emphasize the importance of updating software before accessing emails or the internet.
2. Phishing Awareness: Educate users to be cautious of unsolicited emails, even if they appear to originate from known contacts. Avoid opening attachments or clicking on suspicious links within them. If unsure about the legitimacy of a URL, access the website directly through your browser.
3. Restrictive Measures: Block access to potentially risky content such as Tor, Peer-to-Peer (P2P), and torrent traffic on network devices.

Data Backup and Recovery:

1. Regular Backups: Regularly back up critical data to minimize potential losses due to ransomware attacks and expedite the recovery process. Store backups on separate devices and preferably offline for added security.
2. Data Integrity Checks: Regularly verify the integrity of stored data to detect unauthorized modifications or suspicious activity.
3. Backup Verification: Periodically check backup files for unauthorized encrypted content or malicious elements like backdoors or malicious scripts.

Additional Security Measures:

1. Email Authentication: Implement a Sender Policy Framework (SPF) to prevent email spoofing, a common tactic used by ransomware attackers to deliver malicious emails.
2. Application Whitelisting: Implement application whitelisting or enforce Software Restriction Policies (SRP) to restrict unauthorized applications from running, specifically on locations like %APPDATA% and %TEMP% folders, which are frequent targets for ransomware.
3. Block File Types: Block attachments with potentially risky file extensions such as exe, pif, tmp, url, etc.
4. Disable Risky Features: Disable ActiveX content in Microsoft Office applications and consider disabling remote desktop connections if not essential. Employ least-privileged accounts and limit access to remote desktop functionality.
5. Network Access Control: Restrict access to specific network resources using firewalls and allow connections only from authorized endpoints. Consider employing a dedicated VPN pool for remote desktop access.
6. Strong Authentication: Utilize strong authentication protocols like Network Level Authentication (NLA) in Windows to enhance security.