Why BEC is today’s biggest email threat

Business Email Compromise (BEC) is one of the most costly and insidious cyber threats organizations face. According to the 2024 FBI IC3’s Internet Crime Report, companies lost $2.8 billion to BEC attacks in 2024 alone, contributing to a cumulative loss of $17.1 billion since 2015. These attacks exploit the core of business operations: human trust, financial workflows, and organizational communication.

For CISOs and security leaders, ignoring BEC is no longer an option. The sophistication of attacks has escalated, and the tools and strategies that once worked are increasingly insufficient. Organizations must now think beyond legacy email security and invest in proactive, AI-driven defenses that protect employees and stakeholders alike.

The human element of BEC

What makes BEC so dangerous is that it doesn’t rely on malware, malicious attachments, or even suspicious links. Instead, it preys on human behavior: trust, urgency, and authority. Attackers impersonate executives, vendors, or internal colleagues and craft messages that compel employees to take action without hesitation.

Common BEC scenarios include:

• Invoice fraud: Employees are tricked into wiring funds to fraudulent accounts.
• Payroll diversion: Attackers redirect employee salaries to their own accounts.
• Executive impersonation: Hackers pose as C-level executives, requesting sensitive financial or operational actions.

Unlike traditional attacks, BEC can slip through firewalls and filters because it doesn’t necessarily trigger technical alarms. BEC attacks often succeed precisely because they look legitimate and come from trusted sources. Even the most security-aware employees can fall victim when messages are carefully crafted to exploit organizational hierarchies or urgent deadlines.

This human-centric approach is why training alone is no longer sufficient. Organizations must combine awareness programs with technology that can detect subtle anomalies and patterns indicative of compromise.

Related: Examples of business email compromises

Why traditional email defenses fall short

Legacy email security tools, Secure Email Gateways (SEGs), signature-based filters, and link scanners, were designed to detect malware, spam, and known threats. They are not equipped to handle the subtlety of BEC emails. 

Consider this: many BEC attacks are plain-text emails from legitimate domains, with no attachments or suspicious URLs. To a conventional filter, these messages appear safe, allowing them to land directly in employees’ inboxes.

As a result, the burden falls on human recipients. Employees are expected to notice anomalies, verify sender identity, and resist social engineering cues, all while performing their daily responsibilities. Even well-trained staff can make mistakes, particularly under pressure or tight deadlines.

For security teams, this also creates a challenge: they must proactively prevent attacks while managing the operational overhead of detection and response when humans inevitably err.

Security awareness and training

Since BEC relies on a willing (though unwitting) victim, user awareness is just as important as technical controls. Employees should be trained to recognize warning signs such as:

• Suspicious executive requests: For example, a CEO asking for individual employee W-2s is highly unusual. While urgent requests from senior leadership carry weight, staff should consider whether the ask aligns with normal responsibilities.
• Confidentiality clauses: Impostor emails often instruct recipients not to share the request with anyone else.
• Bypassing standard processes: Most companies require payments and transfers to go through accounting systems. Any direct request to “skip the usual process” should raise alarms.
• Language and formatting issues: Unusual grammar, date formats (e.g., European DD/MM/YYYY), or odd sentence structures can indicate impersonation, even as AI-generated emails make these clues less obvious.
• Lookalike domains and mismatched reply-to addresses: Attackers frequently register near-identical domains (yourc0mpany.com vs. yourcompany.com) to fool distracted employees.

User training should emphasize what to spot and how to respond, including escalation procedures and when to flag suspicious requests to IT or finance.

Process controls

Even the best defenses can fail if organizational processes are weak. That’s why effective BEC mitigation includes rigid verification protocols:

• Strict payment verification procedures for wire transfers and account changes.
• Callback verification using pre-approved contact numbers, rather than replying to the suspicious email itself.
• Dedicated incident response plans for BEC scenarios, so employees know exactly what steps to take if they suspect fraud.
• Regular audits of email systems and financial workflows to identify vulnerabilities before attackers do.

By embedding these safeguards into everyday operations, organizations ensure that even if a fraudulent request reaches an employee, it cannot succeed without secondary verification.

How Paubox’s Inbound Email Security can help

In the fight against Business Email Compromise (BEC), technology that can understand nuance and context is essential. Traditional filters often miss messages that appear normal, so attackers slip through. Paubox’s Inbound Email Security is designed to plug those gaps by combining AI, pattern recognition, and domain protections. Below is how it works and how it adds resilience.

Core features and capabilities

Paubox packages Inbound Email Security with its Email Suite (Plus and Premium tiers). 

Key components include:

• Generative AI detection: The system doesn’t simply rely on keyword rules; it uses generative AI to analyze tone, intent, sender behavior, and contextual anomalies. That means it can detect BEC attempts that deviate subtly from normal communication patterns. It compares incoming messages to historical patterns to flag messages that look out of place. 
• ExecProtect and ExecProtect+ (anti-spoofing / display name protection): A frequent BEC tactic is display name spoofing, making a message appear from an executive or trusted employee. Paubox counters this with ExecProtect, and its enhanced version, ExecProtect+, automates the protection by detecting internal senders and adding them to protected lists. 
• Virus, malware, and phishing scanning: Attachments, embedded macros, and links—all inbound content is scanned. Messages failing checks are quarantined. 
• Custom block/allow rules and quarantine management: Administrators can tailor block/allow rules for domains, senders, or even content patterns. Quarantine review and release tools allow oversight. 
• Transparent decisioning and insights: One of the differentiators is that Paubox provides transparent explanations (headers or logs) for why a message was flagged, with confidence scores and rationale. That insight helps security teams understand and refine defenses. 
• Continuous learning and adaptation: The AI model updates itself, learning from false positives, new threats, and evolving communication patterns, so defenses improve over time. 
• Compliance, privacy, and integration: Paubox is built with HIPAA compliance in mind, ensuring that sensitive data, such as PHI, isn’t exposed through third parties. It integrates smoothly into existing email environments like Microsoft 365 or Google Workspace.

Go deeper: Inbound Security: Overview

FAQS

What is Business Email Compromise (BEC)?

BEC is a type of cyberattack where criminals impersonate trusted figures, like executives, vendors, or partners, to trick employees into transferring money, sharing sensitive data, or clicking malicious links. Unlike typical phishing, BEC doesn’t always include malware or suspicious attachments, making it harder to detect.

What should I do if my business falls victim to a BEC attack?

• Report the incident immediately to your IT/security team and the FBI’s IC3 unit. 
• If payments have been made, contact your bank to try to recall the transaction. 
• Conduct an internal investigation to understand how the attack succeeded and take steps to strengthen defenses to prevent recurrence.

Is BEC only about money theft?

No. While financial fraud is the most common motive, BEC can also be used to steal sensitive information, manipulate supply chain communications, or gain insider access to systems. Any action that relies on email trust can be exploited.