Detection Method: Whois

Whois analysis retrieves and examines domain registration information from global Whois databases to spot suspicious or recently created domains that could indicate phishing attempts. This method helps you understand key domain details like the age, ownership, and registration patterns, which can be red flags for malicious activity.
Whois analysis can detect:
  • Newly registered domains that might have been set up just for phishing campaigns
  • Domains with suspicious registration patterns or incomplete Whois records
  • Mismatched registration details that don’t align with the claimed organization
  • Domains registered via privacy services to conceal true ownership
  • Domains with upcoming expiration dates, which could indicate temporary use
For example, established organizations often use domains that have been registered for long periods. So, if you get an email from a financial institution using a domain that was registered only a few days ago, that’s a huge red flag.
Rule Name & Severity
Last Updated
Author
Types, Tactics & Capabilities
Link: Financial account issue with suspicious indicators
6d ago
Mar 24th, 2026
Sublime Security
Service abuse: Google Firebase sender address with suspicious content
18d ago
Mar 12th, 2026
Sublime Security
Link: Commonly Abused Web Service redirecting to ZIP file
20d ago
Mar 10th, 2026
Sublime Security
Link: Multistage landing - ClickUp abuse
1mo ago
Feb 27th, 2026
Sublime Security
Attachment: PDF with multistage landing - ClickUp abuse
1mo ago
Feb 27th, 2026
Sublime Security
New link domain (<=10d) from untrusted sender
1mo ago
Feb 6th, 2026
Sublime Security
Attachment: Legal themed message or PDF with suspicious indicators
1mo ago
Feb 5th, 2026
Sublime Security
Vendor impersonation: Thread hijacking with typosquat domain
2mo ago
Jan 12th, 2026
Sublime Security
Attachment: DocuSign impersonation via PDF linking to new domain
2mo ago
Jan 12th, 2026
Sublime Security
BEC/Fraud: Urgent language and suspicious sending/infrastructure patterns
2mo ago
Jan 12th, 2026
Sublime Security
Suspicious newly registered reply-to domain with engaging financial or urgent language
2mo ago
Jan 12th, 2026
Sublime Security
Brand impersonation: Microsoft fake sign-in alert
2mo ago
Jan 12th, 2026
Sublime Security
Link: Google Firebase dynamic link that redirects to new domain (<7 days old)
2mo ago
Jan 12th, 2026
@ajpc500
Suspected lookalike domain with suspicious language
2mo ago
Jan 12th, 2026
Sublime Security
VIP impersonation: Fake thread with display name match, email mismatch
2mo ago
Jan 12th, 2026
Sublime Security
Fraudulent order confirmation/shipping notification from Chinese sender domain
2mo ago
Jan 12th, 2026
Sublime Security
Brand impersonation: Silicon Valley Bank
2mo ago
Jan 12th, 2026
Sublime Security
Link: Cryptocurrency fraud with suspicious links
3mo ago
Dec 1st, 2025
Sublime Security
Service abuse: Google Drive share from new reply-to domain
4mo ago
Nov 13th, 2025
Sublime Security
Spam: Fake photo share
4mo ago
Nov 8th, 2025
Sublime Security