With technology constantly evolving, cyber threats have kept pace with the world-wide web’s rapid progression. One form of attack that has significantly proliferated today is ransomware. This malicious software infiltrates computer systems, encrypts files, and demands a ransom for their decryption.

The New Age of Ransomware
Ransomware attacks have undoubtedly risen and evolved with time, becoming increasingly sophisticated in evading traditional security defenses like antivirus software and firewalls. From broad-brush blitzkriegs, attackers are adopting a more targeted approach now – “big game hunting.” They’re focusing on organizations that can afford to pay large ransoms rather than casting a wide net.

Evasion Tactics
Recently developed strains exploit system vulnerabilities to bypass existing security measures. Malicious code is obfuscated or delivered via stealthy vectors like spear phishing or zero-day exploits. Today’s ransomware uses techniques like living-off-the-land (using legitimate tools to carry out nefarious activities) and fileless attacks (residing in system memories) to stay under the radar. As such, conventional defense mechanisms are usually ill-equipped to tackle these evolved threats.

CISO’s Role in Overcoming Ransomware Threat
Given the rising menace of sophisticated ransomware attacks, the role of a Chief Information Security Officer (CISO) becomes crucial. Here’s how they can respond:

1. Awareness Training: Imparting awareness training should be central to every CISO’s strategy. Teach employees about safe online practices which include not clicking suspicious links or opening unknown attachments.

2.Reducing Attack Surface: Minimize potential points of intrusion by managing the use of privileged accounts and blocking unused ports.

3.Backup Strategy: Ensure regular data backups are done both on-premises and in cloud environments for easy recovery post-incidents.

4.Patching and Updates: Regularly update and patch all systems. This can prevent intrusion through known vulnerabilities.

5.Advanced Security Systems: Use next-gen security systems with behavioural analytics, threat intelligence, and machine learning capabilities. These can detect unusual activities and mitigate threats before they wreak havoc.

6.Incident Response Team: Establish a dedicated cyber incident response team that can swiftly contain the attack and recover operations.

7.Insurance: Cyber insurance is another aspect to consider, providing cushioning for any potential financial damages.

8.Cooperation: Create partnerships with other organizations for sharing threat intelligence.

Ransomware attacks today are perpetually morphing, evading classic antivirus solutions by exploiting unsuspected weaknesses in IT infrastructures. As CISOs, it’s vital to anticipate these changes and stay one step ahead of cybercriminals. By fostering awareness among employees, employing advanced defensive mechanisms, and robust response strategies, businesses can stand strong in the face of future ransomware onslaughts.