Detecting Lookalike and Homoglyph Domains Targeting Corporate Brands
How attackers exploit internationalized domain names (IDN) and visual similarities to deceive employees and clients, and how to defend against them.
The Art of Visual Deception
Homoglyph attacks exploit characters from different alphabets (such as Cyrillic or Greek) that look identical to standard Latin characters. To an unsuspecting employee, `microsоft.com` with a Cyrillic 'о' appears indistinguishable from the legitimate domain.
Continuous External Domain Monitoring
Organizations should implement automated monitoring of newly registered domains, Certificate Transparency logs, and DNS changes to detect lookalike registrations within hours of their creation.
Inbound Mail Filter Protections
Configure inbound mail security gateways to reject or heavily flag incoming messages originating from domains registered within the last 30 days or displaying high Levenshtein distance similarity to corporate and partner domains.
Related Articles & Advisories
SPF, DKIM & DMARC: Stopping Domain Spoofing and Executive Impersonation
Why traditional spam filters fail against spoofed domains, and how enforcing DMARC p=reject stops attackers from impersonating your executive team and company brand.
The Road to DMARC Enforcement: Migrating from p=none to p=reject Safely
A phased methodology for cataloging third-party senders, aligning cryptographic keys, and enforcing zero-tolerance rejection without dropping legitimate mail.
Business Email Compromise (BEC): Anatomy of Invoice Redirection Wire Fraud
How cybercriminals intercept supplier email threads, manipulate banking details, and siphon millions through synthetic invoice redirection.