YUDU Sentinel Blog

Cyber or Ransomware Attack? You need Out-of-Band Communications to Respond

Written by Richard Stephenson | 09 Oct 2025

Why an Out-of-Band Communication System is the Only Secure Way to Respond

In today’s digital landscape, cyber and ransomware attacks are becoming increasingly sophisticated. One of the primary tactics attackers use is to disrupt or compromise an organisation’s internal communication systems, leaving teams unable to coordinate effectively.

In such scenarios, relying on traditional communication channels, such as email or standard messaging platforms, can exacerbate the problem. That’s where out-of-band communication systems come into play.

What Is Out-of-Band Communication?

Out-of-band communication refers to any form of communication that is separate from normal communication channels. This could include platforms like WhatsApp, Signal, Telegram, or even Facebook. However, from a corporate perspective, using such informal platforms raises concerns about security, compliance, and accountability.

While these tools might allow teams to stay connected during an attack, they fall short in ensuring that the communication is secure, encrypted, and auditable. That’s why businesses need a dedicated platform designed for out-of-band communication that offers the same level of discipline and compliance as their primary systems.

Why Sentinel Is the Ideal Out-of-Band Communication Platform for Cyber Response

Sentinel was specifically designed to be an out-of-band communication system, providing a secure and auditable platform that comes into its own during a cyber or ransomware attack.

When attackers target your organisation, their primary goal is to cripple your ability to communicate. This strategy amplifies the chaos, making it incredibly difficult for your resilience and cyber response teams to coordinate effectively and resolve the issue. By compromising primary communication channels—whether through email or internal chat platforms—attackers ensure their disruption has maximum impact.

However, when you switch to an out-of-band system like Sentinel, you immediately regain control of your communication and coordination processes. Sentinel enables secure, encrypted communication that attackers cannot access, ensuring your teams can continue working efficiently during the most critical moments of an incident.

The Challenges of Using Ad-Hoc Out-of-Band Communication Platforms

While using platforms like WhatsApp or Signal might seem like a quick fix, these tools come with several risks when used in a corporate environment. They are often unregulated, lack the necessary auditability, and can leave communication threads scattered across multiple platforms. This makes it difficult to maintain compliance and accountability, both of which are critical in the aftermath of an attack.

Without a central, compliant out-of-band system, post-incident audits become nearly impossible. Tracking decisions, verifying actions, and understanding the flow of communication during the event can be disorganised at best—and entirely absent at worst.

How Sentinel Ensures Security, Accountability, and Compliance

Sentinel eliminates these risks by providing a pre-activated out-of-band communication system that is ready for deployment the moment your organisation detects an attack. It centralises all necessary contacts, staff information, business continuity plans, and crisis response strategies into one secure platform.

Key features include:

  • Mass notifications to communicate with the entire organisation instantly.
  • Secure chat environments to discuss sensitive matters without fear of eavesdropping.
  • Action cards and business plans readily available for offline access, ensuring continuity even if primary systems are compromised.

Sentinel’s encryption and secure auditing features guarantee that all communications during the incident are logged and protected, offering a comprehensive record of how the attack was managed. This not only enables a swift resolution but also provides crucial data for post-incident reviews—a critical element in improving future incident responses.

The True Cost of Communication Errors During an Attack

During a ransomware or cyber attack, mistakes made due to poor communication can significantly increase the cost and impact of the event. Miscommunications, delays in response, and missed instructions can compound the damage already being done by the attackers. By ensuring swift, secure communication across your team, Sentinel reduces the likelihood of such costly errors and helps restore order quickly.

Beyond Cyber: The Importance of Out-of-Band Communication in Other Incidents

Out-of-band communication systems are not just for cyber incidents. Power outages, server failures, or other major incidents can also leave your organisation unable to access primary communication systems. In these situations, having a separate communication platform like Sentinel ensures that teams can continue coordinating their responses effectively.

Cyber Attackers Target Communication First—Be Prepared

It’s important to remember that attackers deliberately target your organisation’s ability to communicate during a cyber or ransomware attack. This is no accident—it’s a calculated move to cause maximum disruption. Infecting emails, infiltrating internal chat systems like Slack or Microsoft Teams, and monitoring your unencrypted communications is a common tactic.

Once an attack has been identified, it is critical to move all incident management and communications away from these compromised channels. Sentinel provides an encrypted, secure, out-of-band communication system that ensures your organisation can respond effectively while keeping attackers out of the loop.

Conclusion: Out-of-Band Communication Is Essential for Cyber Resilience

In the modern threat landscape, an out-of-band communication system is no longer a luxury—it’s a necessity. As cyber and ransomware attacks continue to evolve, so must our defences. Sentinel provides a secure, compliant, and resilient platform for managing communication during an attack, ensuring that your team can focus on resolving the incident rather than struggling to communicate.

Don’t let attackers control your communication—be prepared with Sentinel.