Why Email Remains the Weakest Link - and What Smart Organizations are Doing About It

Despite numerous advances in cybersecurity, email remains the easiest way for attackers to infiltrate an organization’s network. This is because modern email threats appear legitimate due to spoofing and social engineering tactics.

However, modern email-borne threats can be managed with the right strategy. This article highlights the limitations of standard email defense and ways to strengthen the email perimeter without disrupting employees’ productivity.

The Problem: Why Email Remains the #1 Entry Point for Hackers

Email became a core part of business communication in the late 1990s and has been ever since. It remains the most recognized and widely used communication channel in business - that makes it an irresistible target.

Unlike infrastructure such as systems or servers, which can be secured, email relies on human interaction: reading, clicking, replying, downloading. And that’s where attackers strike. All it takes is one employee opening the wrong message.

Today’s email-borne threats go far beyond spam and obvious phishing tactics. Targeted attacks like Business Email Compromise (BEC) impersonate trusted vendors or executives and use social engineering to trick employees into sending funds or sensitive data. Moreover, ransomware often arrives as a seemingly harmless link or attachment, unleashing damage with a single click. BEC exploits employee trust, while ransomware leverages speed to act on a single careless click.

For small to medium-sized businesses, a single email-borne cyberattack can mean compliance violations, legal risk, reputational damage, and significant financial loss. In 2024 alone, the FBI’s Internet Crime Complaint Center recorded $2.7 billion in losses from Business Email Compromise, making it the second costliest cybercrime after investment scams.

Despite the clear vulnerabilities in email security, many enterprises still rely on basic spam filters and surface-level IT training to prevent malicious actors from getting in.

Why Standard Defenses No Longer Stop Modern Email Threats

Outdated tools miss sophisticated threats

Legacy email defenses like spam filters, antivirus tools, and static blocklists can’t keep up with today’s advanced threats. While they’re effective at catching junk mail and obvious malware, most malicious emails no longer fit that mold. In fact, only 1% of malicious emails that reach inboxes carry malware, according to Fortra's 2025 email threat intelligence report.

The vast majority, such as Business Email Compromise, domain spoofing, and credential phishing, often slip through the cracks because they use plain text and are crafted to look entirely legitimate.

Standalone tools can’t stop multi-stage attacks

Most email security tools used in today’s organizations work in isolation. They typically focus on a single layer, like filtering inbound messages or scanning attachments. But the truth is such one-dimensional defenses create blind spots between inbox and endpoint.

Once a malicious email gets past the inbox, the threat doesn’t stop - it instead moves laterally within the network, leaving behind a trail of multi-stage attacks. It often starts with a seemingly legitimate email. But that’s how attackers gain a foothold, stealing credentials and eventually breaching your endpoints.

Training alone is not a firewall

More organizations are prioritizing security awareness training for employees. This goes a long way to reduce the likelihood of falling for phishing scams, but it’s not enough. Even well-trained employees are prone to human error, especially those in non-technical fields. Under pressure, they might click the wrong link or mistakenly trust an impersonation.

Attackers know this and craft their emails accordingly to bypass technical and human defenses.

Delayed detection gives threats a head start

Most legacy security setups are reactive - they trigger alerts only after a threat has landed in the inbox or a user has already clicked something. Cybercriminals, on the other hand, move quickly, meaning that the damage may already be underway by the point of detection.

Take NioCorp for example. In February 2025, the North American minerals company recorded a $500,000 loss after a Business Email Compromise led to rerouted vendor payments. Although the company discovered the breach internally, the money was already in motion.

A Smarter Defense: Securing Email with Layered Protection

Strengthening the email perimeter with authentication and filtering

Smart organizations are deploying authentication protocols (e.g., Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication Reporting and Conformance (DMARC)) to block spoofed messages before they reach users.

They also rely on secure email gateways to filter email traffic, identifying and curbing threats at the front door.

Combining authentication and email filtering creates a double layer of protection, securing the company’s email perimeter.

Coordinating defense across email, identity and device

Dismantling security silos is necessary for preventing blind spots that attackers can slip through. To match the rapidly evolving sophistication of cybercriminals, modern organizations must create a fast, coordinated defense setup - one that integrates email, identity and endpoint systems. Linking email filtering with identity verification and endpoint monitoring allows security teams to catch suspicious login attempts before any damage is done.

For instance, integrated platforms can trigger multi-factor authentication once a suspicious email is detected, resulting in credentials being revoked if the user fails to verify their identity.

A multi-layer defense strategy like this one covers the entire attack chain, from inbox to endpoint.

Adapting security protocols to withstand evolving threats

As we’ve already established, malicious actors are constantly modifying their methods to infiltrate the security barriers in place today. This is why companies’ in-house security protocols must move with the times as well.

For companies seeking to evade polymorphic attacks, Microsoft recommends an adaptive approach, powered by advanced Machine Learning (ML) and Natural Language Processing (NLP). These behavior-based detection methods analyze email content in real-time and flag social engineering attempts, even in plain-text or payload-free messages.

Results: Reduced Risk, Better Resilience

Organizations that implement layered, adaptive defenses as we’ve previously discussed generally have formidable email perimeters that can largely withstand threat actors.

Combining integrated response, security training (for employees), and email filtering can shift a company’s security approach from reactive to proactive - stopping attacks before they happen.

All these methods together create positive outcomes like:

• Fewer successful Business Email Compromise and phishing attempts
• Faster detection and response to probable threats
• Reduced exposure to fraud and data loss
• Reduced risk of regulatory penalties and operational downtime
• Limited blast radius when hackers get in

Key Takeaways

• Email isn’t going away anytime soon, and neither are hackers.
• As Business Email Compromise, phishing and spoofing tactics continue to evolve, so must your defenses.
• A layered, proactive cybersecurity strategy is the only true defense against email-borne threats.

Considering the growing cyberattacks carried out via email, Paratus Cybersecurity has partnered with leading email security providers to mitigate unauthorized access, hinder spoofing and safeguard your company from BEC attacks. Get in touch with us to protect your company’s digital assets and reputation in the long term.