DefendTM
Advanced Inbound Email Threat Defense
Stop the breach today while building a more intuitive, security-aware workforce for tomorrow.
AI-Powered Email Security That Understands Humans
Today’s most dangerous threat is the bad actor with a good identity. KnowBe4 Defend moves beyond black-box decision-making by using behavioral AI and natural language processing (NLP) to map historical communication patterns to make smarter, more informed autonomous decisions. By identifying anomalies in intent and linguistic patterns, Defend catches more payload-free BEC and supply chain attacks that other layers miss.
Key Benefits of KnowBe4 Defend
Catch the 30%+ of Threats Others Miss
On average, 12 phishing emails slip through M365 and SEG filters for every 10,000 received. Neutralize them before they reach the inbox.
97% Reduction in Clicking Malicious Links
Stop users from proceeding with risky actions through high-visibility, real-time localized teachable moments.
Industry-Leading Versatility
The only vendor offering a choice between SMTP and Graph API deployments, both featuring real-time, point-of-risk user education.
95% Operational Time Savings
Shift to a Human-on-the-Loop model. Let AI handle threat containment and triage, saving a 1,000-user organization 45 hours of weekly response time.
1.4 Billion Graymail and Spam Filtered per Year
Drastically reduces alert fatigue and inbox overload by removing millions of non-malicious distractions from your environment.
Localized Teachable Moments
Defend empowers your global workforce by moving beyond generic translation by using rewritten native content built for your workforce across the globe.
No Update Time for Zero-Day Detection
AI detects the building blocks of phishing attacks without relying on reactive rule updating.
How Does KnowBe4 Defend Work?
Analyze
Defend's relationship DNA identifies shifts in tone or urgency: key indicators of compromised legitimate accounts.
Alert
Color-coded Outlook Category Tags or interactive banners provide visual cues in the inbox, allowing users to identify threats before reading the email.
Educate
Automated teachable moment emails provide detailed overviews tailored to each user to increase workforce vigilance.
Remediate
Collapses thousands of related threats into a single investigative view for mass, one-click remediation.
Deploy Your Way
Defend SMTP Email Flow
Inbound Email
Phish threats enter mailflow
Microsoft 365
DEFEND
AI-Powered Phish Detection
User Inbox
Benign & Suspicious
Quarantine
Dangerous Threats
Graph API Email Flow
Inbound Email
Phish threats enter mailflow
Microsoft 365
User Inbox
User Inbox
Benign & Suspicious
DEFEND
AI-Powered Phish Detection
Quarantine
Dangerous Threats
Post-Delivery: Leverages API for analysis without altering mail flow.
Gmail Email Flow
Inbound Email
Phish threats enter mailflow
User Inbox
User Inbox
Benign & Suspicious
DEFEND
AI-Powered Phish Detection
Junk
Dangerous Threats
Post-Delivery: No Quarantine, send Dangerous to Junk.
Strategic Metrics to Track with Defend
Defend allows your business to decouple growth from risk. As your headcount and revenue scale, your security incidents shouldn’t.
Incident Growth vs. Company Growth
Use behavioral AI and NLP to detect the 30%+ of sophisticated, polymorphic AI attacks that others miss. This ensures that increasing your headcount doesn't lead to a corresponding spike in breach activity.
Automated Response vs. Human Response
Create a Human-on-the-Loop model where Defend offloads the operational weight of triage to intelligent, autonomous systems. Detailed reporting provides visibility into which users are targeted and where to provide tailored, high-impact training.
Capacity Management
Visualize your productivity savings in relation to incoming alerts. This allows you to reshift your SOC team’s focus to pressing matters by automatically removing 35% of email noise from graymail and spam across all your employees' mailboxes.
Global Scalability
Protect employees across the globe with localized teachable moments that drive real behavior change.
Key Features
Strategic Visibility & ROI Reporting
- Quantify your SOC’s impact with boardroom-ready data. Visualize the exact volume of noise and threats removed from user inboxes.
- Measure Productivity: Inform stakeholders exactly how much time and money the organization is saving by automating email security.
- Capacity Management: Use precise metrics to understand the ratio of incoming alerts to SOC bandwidth, allowing you to reshift focus from manual triage to high-value strategic initiatives.
AI-Driven Threat Detection & Relationship DNA
Catch the 30%+ of threats traditional secure email gateways (SEGs) miss. Defend uses self-learning AI and natural language processing (NLP) to map the historical communication patterns between your employees and their contacts.
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Linguistic Anomaly Detection: Identifies sudden shifts in tone or urgency: the primary indicators of a compromised legitimate account (BEC).
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Lower Attacker Dwell Time: Detect the low-and-slow lateral movement and zero-day campaigns instantly, dramatically reducing your Mean Time to Detect (MTTD).
Native Teachable Moments Localization
Empower your global workforce with security insights that actually land, not generic translations. Defend uses rewritten native content built for your global workforce.
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Regionally Appropriate Accuracy: Provide nuanced language support in Brazilian Portuguese, Chinese (Mandarin-Simplified), Dutch, English, French, French Canadian, German, Hungarian, Italian, Japanese, Norwegian, Spanish and Spanish (Latin America).
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Reduced Admin Overhead: Prevent non-English speaking users from overwhelming IT with questions by providing clear, native-language explanations for why an email was deemed dangerous.
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Global Program Completeness: Run a unified training program across all key regions without gaps, ensuring behavior change is driven even in high-revenue international markets.
Seamless Integrations and Campaign-Level Scalability
Minimize context switching and eliminate admin friction. Defend offers industry-leading deployment versatility with both Graph API and SMTP options.
- Organize and Respond: Collapse thousands of polymorphic threats into a single investigative view, applying mass remediation with one click to ensure consistent incident response process adherence.
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Native Microsoft Defender Quarantine Sync: Pushes threat verdicts directly into Microsoft Defender quarantine console, allowing your team to operate within a single, unified workflow.
Real-Time User Empowerment and Teachable Moments
Turn your workforce into a security asset. Instead of black-box security that silently quarantines, Defend provides interactive teachable moments to keep end users alert, engaged and aware of the threats in their inbox.
- Humans-in-the-Loop: Color-coded banners and tags stop 97% of users from proceeding with risky actions. Automated teachable moments explain the why behind an action.
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Boosted eNPS: Transform the security team from a bottleneck into an educational partner, building a positive relationship between the SOC and the business through transparency and empathy.
Trusted by Customers
Defend’s value is proven every day in the statistics shown in its threat intelligence dashboard. The banners have also dramatically increased employees’ everyday vigilance to phishing attacks.
The City of Edinburgh Council | Mark Burtenshaw, ICT Manager Security and Compliance
We recognized that one layer is not enough to detect and neutralize the numerous advanced phishing threats targeting GMMH day-to-day work. KnowBe4 Defend not only provides an additional layer of defense but also supplements our security awareness training. Defend’s clickable banners allow employees to continuously develop their cybersecurity awareness.
GMMH | Kevin Orritt, Cyber Security Manager
We were looking for a new solution that went above and beyond the SEG – and that’s exactly what Defend has given us. It has optimized every aspect of our email security, from detection and remediation to security awareness training.
Shields Health Solutions | Principal Security Engineer
The prompts are one of the things that drew us to [Defend]. We want to allow employees to find those smaller breadcrumbs and really help find anything that might be a very elusive-type of risk.
First Community Credit Union | Bryan Perkola, Senior VP of Information Security
Industry Recognition

KnowBe4 named a Leader in Gartner® Magic Quadrant™ for Email Security Platforms
KnowBe4 has been named a Leader in the 2025 Gartner® Magic Quadrant™ for Email Security Platforms for the second consecutive year — and we're offering you complimentary access to the full report.
See KnowBe4 Defend™ in Action
Learn how Defend™ strategically enhances Microsoft 365 native security to catch the threats Secure Email Gateways (SEGs) and others miss.
Gartner, Gartner Peer Insights ‘Voice of the Customer’: Email Security Platforms, Peer Contributors, July 4, 2025.
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