HIPAA constrains content and requires encryption in transit and audit trails.
What lookalike domain spoofing is#
Lookalike (cousin) domain spoofing uses a domain visually similar to yours (examp1e.com, example-billing.com) to send mail that passes authentication for the attacker's domain while impersonating your brand.
Why it matters#
DMARC stops exact-domain spoofing, so attackers moved to lookalikes. It is now the dominant brand-impersonation technique.
Implementation plan for healthcare organizations#
- Register the most obvious typo and hyphen variants of your domain.
- Monitor new registrations that contain your brand string.
- Configure inbound gateway rules to flag display names matching executives from external domains.
- Train finance and executive assistants specifically on this pattern.
Priorities specific to healthcare organizations#
HIPAA constrains content and requires encryption in transit and audit trails. Weight your effort toward the steps above that address this constraint first, and measure with metrics that match how healthcare organizations generate value from email.
Common mistakes#
- Assuming DMARC p=reject protects against lookalikes.
- Registering variants but leaving them without DMARC reject themselves.
Frequently asked questions#
How many lookalike domains should I register?
The top 10 to 20 variants by likelihood is a reasonable start; monitoring covers the long tail.