Why Voice Security Can't Stay on Hold Any Longer

A few years ago, the idea of someone faking your CEO's voice to wire millions of dollars might've sounded like the plot of a cyber-thriller. Now, it's an everyday risk.

In early 2024, robocalls using an AI-generated clone of President Joe Biden's voice urged voters to skip a primary election. Around the same time, multiple global enterprises reported deepfake voice scams in which bad actors impersonated executives to authorize fraudulent payments and extract sensitive data from employees.

These incidents highlight a growing reality: voice is the last major communications channel without mature, standardized security controls. And thanks to generative AI (GenAI), it's now being targeted at scale by adversaries who are faster, cheaper and more convincing than ever.

For voice, cyber and network teams, that means one thing — the era of treating voice as a "non-priority" security layer is over. To keep pace, these teams must move beyond point solutions and static architectures by revisiting, updating and integrating their voice security stack today. 

The new threat landscape

While voice threats aren't new, their speed, scale, and sophistication have changed dramatically. In the past year alone, vishing (voice phishing) attacks surged more than 400%, with success rates now exceeding those of email phishing campaigns.

The most pressing enterprise voice threats emerging today include:

• Toll fraud and call spoofing: Malicious actors exploit VoIP systems and Session Border Controllers (SBCs) to generate or reroute fraudulent calls, often leaving organizations with six- or seven-figure losses in telecom charges.
• Vishing and social engineering: Using publicly available voice samples or AI-generated clones, criminals impersonate trusted leaders or vendors to extract credentials, initiate wire transfers or reset access controls.
• Deepfake voice attacks: Adversaries can now easily create convincing voice clones  to impersonate executives, spread misinformation and even fake job interviews to infiltrate organizations.
• Insider and hybrid threats: Voice systems, videoconferencing and chat messaging are increasingly integrated with collaboration platforms like Microsoft Teams, Zoom, WhatsApp, Apple Messages for Business, Webex and Google Meet, enabling insider or compromised-account misuse through channels that lack consistent monitoring and authentication.
• Robocalls and spam flooding: Mass robocall campaigns can overwhelm voice infrastructure and degrade service quality, functioning as a form of distributed denial of service (DDoS) for telephony.

Who's at risk? 

According to Keepnet's Voice Phishing Response Report, 70% of organizations are at risk for a voice attack.

While contact centers have long been the obvious attack surface, the threat landscape has expanded. Industries where trust, identity and timing are critical are seeing the steepest rise in voice-borne fraud and data theft. 

For example, in wealth management and banking, threat actors are impersonating clients and executives to divert funds and approve fake transactions. In healthcare, we're seeing voice-based prescription fraud and patient data breaches. Corporate IT help desk agents are being tricked into resetting employee passwords, and HR departments are dealing with fake interviews via deepfake voices, hoping to extract IP or credentials. 

Given these risks and the increasing volume and sophistication of attacks, technical teams need a new approach that's flexible and built for the realities of today's threat landscape. 

A holistic and modular framework for voice security

At WWT, many of our clients come to us with a single pain point, such as robocalls overwhelming their contact center, outbound calls being ignored due to poor caller reputation or executive impersonation attempts. But rarely are these teams thinking holistically about voice security. This is a mistake, and why we built a lab environment in our Advanced Technology Center around a flexible, modular framework. 

Rather than prescribing a specific vendor or locking organizations into a rigid architecture, our holistic voice security framework — where components can be swapped in and out — offers a starting point that helps teams act now while staying adaptable as threats and technologies evolve. 

Foundational elements of voice security

Our framework consists of several core elements that, when combined, create a more resilient and adaptable voice security posture. Your organization likely has some of these components in place already, while others may need to be added or upgraded. 

Voice traffic filtering

This is often the first line of defense. Filtering solutions help identify and block robocalls, spam, and known fraudulent traffic before they reach your internal systems. Many organizations already have some form of call filtering in place, but these tools are often outdated or siloed. Modern filtering should integrate with other layers of your voice environment and support real-time decision-making.

Caller authentication and branding

Spoofed caller IDs are a common tactic in impersonation attacks. Solutions in this category help verify the legitimacy of inbound and outbound calls, often using STIR/SHAKEN protocols, branded calling or behavioral analysis. While STIR/SHAKEN is a good start, it's limited in scope and doesn't cover international or non-participating carriers, so additional layers are often needed.

Deepfake detection

This is one of the fastest-evolving areas of voice security. Bad actors can now generate convincing synthetic voices with just seconds of audio. Deepfake detection tools analyze voice patterns, cadence and other biometric markers to flag suspicious activity. These tools are still maturing, and no single solution is perfect, so it's important to evaluate them carefully and be prepared to swap vendors as the space evolves.

Sentiment and behavioral analysis

While the art of manipulating human emotion is nothing new, today's adversaries are using AI to tailor attacks with precision. Sentiment and behavioral analysis can help detect emotional manipulation, urgency cues or inconsistencies in tone that may indicate social engineering. These capabilities are especially useful in contact centers or high-risk interactions, where subtle shifts in behavior can reveal deeper threats.

Voice recording and post-call analysis

Many organizations already record calls for compliance or training. But few are using that data to improve security. Post-call analysis can surface patterns, identify gaps in detection and feed insights back into your broader security strategy. It's also a critical component for incident response and forensic investigation.

Orchestration and integration layer

This is what ties everything together. Think of it as the traffic cop or control plane that routes calls through the appropriate checks, integrates with your existing voice, communication or security stack, and enables modularity. 

Key considerations when evaluating voice security vendors

New voice security vendors are constantly emerging. In fact, our team is currently monitoring, evaluating and validating more than 100 vendors, with new ones popping up daily. 

This creates a real challenge for technical teams: how do you know where to start, what to prioritize and which tools will still be relevant six months from now?

We advise clients to consider these seven factors when evaluating voice security solutions: 

1. Accuracy: Can it reliably detect threats without drowning your team in false positives?
2. Speed: Can it keep up with your call volume and deliver results in real time?
3. Integration and interoperability: Can it integrate with your existing voice communication and security stack, and work alongside other tools in a modular framework?
4. Explainability: Does it offer transparency into why it flagged a call?
5. Vendor stability: Is the company financially viable and ready for enterprise demands?
6. Ease of use: Will your team actually use it, or is it too complex?
7. Continuous improvement: Does it get smarter over time as your environment changes?

With many voice security solutions still in their infancy, odds are you won't find the "perfect vendor" that checks every box (and that's OK). Start with a flexible foundation, choose tools that fit your current priorities, and be ready to adapt.

Conclusion 

Voice security can't stay on hold. The risks are real, and the next attack could be just a phone call away. With the support of their business leaders, technical teams need to move quickly to build flexible, multi-layered defenses that keep pace with evolving threats and technologies. But you don't have to figure it out alone.

Our team brings decades of experience and a proven track record in helping clients across industries modernize their voice security strategies. Whether you're just starting or looking to strengthen your existing defenses, we can help you assess solutions, test new technologies in our AI Proving Ground and build a framework that's ready for what's next.