• Sublime Core Feed
High Severity

Impersonation: Executive using numbered local part

Labels

BEC/Fraud
Free email provider
Impersonation: VIP
Social engineering
Header analysis
Sender analysis

Description

Detects messages from free email providers where the sender's email address uses a pattern commonly associated with executive impersonation, containing 'chair' or 'ceo' followed by numbers in the local part.

References

No references.

Sublime Security
Created Jan 30th, 2026 • Last updated Jan 30th, 2026
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and sender.email.domain.domain in $free_email_providers
and regex.icontains(sender.email.local_part, '^c(?:hair|eo)\d+')
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