New link domain (<=10d) from untrusted sender
Detects links in the body of an email where the linked domain is less than 10 days old from untrusted senders.
Sublime rule (View on GitHub)
1name: "New link domain (<=10d) from untrusted sender"
2description: |
3 Detects links in the body of an email where the linked domain is less than 10 days old from untrusted senders.
4type: "rule"
5severity: "medium"
6source: |
7 type.inbound
8 and length(body.links) > 0
9 and any(body.links, network.whois(.href_url.domain).days_old <= 10)
10 and (
11 (
12 profile.by_sender().prevalence in ("new", "outlier")
13 and not profile.by_sender().solicited
14 )
15 or profile.by_sender().any_messages_malicious_or_spam
16 )
17 and not profile.by_sender().any_false_positives
18tags:
19 - "Attack surface reduction"
20attack_types:
21 - "Credential Phishing"
22 - "Malware/Ransomware"
23detection_methods:
24 - "Sender analysis"
25 - "URL analysis"
26 - "Whois"
27id: "4805b0e6-6d35-512b-8053-87dd0edacc8a"