• Sublime Core Feed
Medium Severity

Headers: Outlook Express mailer

Labels

BEC/Fraud
Credential Phishing
Malware/Ransomware
Evasion
Spoofing
Header analysis

Description

Detects emails claiming to be sent from Outlook Express, which is a legacy email client that is no longer supported or commonly used.

References

No references.

Sublime Security
Created Nov 6th, 2025 • Last updated Nov 6th, 2025
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and strings.icontains(headers.mailer, 'Outlook Express')
and not profile.by_sender_email().any_messages_benign
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