Medium Severity

Link: Randomly generated subdomain

Labels

Credential Phishing
Evasion
URL analysis

Description

Identifies inbound messages containing links where the subdomain follows a pattern of letters combined with a long hexadecimal string, a hallmark of auto-generated or algorithmically created hosting infrastructure often used to evade detection.

References

No references.

Sublime Security
Created Oct 21st, 2026 • Last updated Oct 21st, 2026
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and any(body.current_thread.links,
        regex.imatch(.href_url.domain.subdomain, '[a-z]{3,30}[0-9a-f]{32}')
)
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