• Sublime Core Feed
Medium Severity

Headers: Invalid recipient domain with mismatched reply-to from new sender

Description

Message sent to an invalid recipient domain with a reply-to address that differs from the sender address, originating from a new sender.

References

No references.

Sublime Security
Created Nov 21st, 2025 • Last updated Nov 21st, 2025
Source
type.inbound
and length(recipients.to) <= 1
and all(recipients.to, .email.domain.valid == false)
and length(headers.reply_to) == 1
and headers.reply_to[0].email.domain.root_domain != sender.email.domain.root_domain
and profile.by_sender_email().prevalence == "new"
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