Detection rules › Sublime MQL

Brand impersonation: Purdue ePlanroom with suspicious links

Severity
medium
Type
rule
Source
github.com/sublime-security/sublime-rules

Detects messages impersonating Purdue ePlanroom with links that either not from the legitimate reprographix.com domain or contain suspicious credential theft indicators.

Threat classification

Sublime's own taxonomy (not MITRE ATT&CK).

CategoryValues
Attack typesCredential Phishing, BEC/Fraud
Tactics and techniquesImpersonation: Brand, Social engineering

Event coverage

Rule body MQL

type.inbound
and strings.icontains(body.current_thread.text, "Purdue ePlanroom")
and (
  any(filter(body.links, strings.contains(.display_text, "Review This Project")),
      .href_url.domain.root_domain != "reprographix.com"
  )
  or any(body.links, ml.link_analysis(.).credphish.disposition == "phishing")
)
and not (
  sender.email.domain.root_domain == "reprographix.com"
  and headers.auth_summary.dmarc.pass
)

Detection logic

Scope: inbound message.

Detects messages impersonating Purdue ePlanroom with links that either not from the legitimate reprographix.com domain or contain suspicious credential theft indicators.

  1. inbound message
  2. body.current_thread.text contains 'Purdue ePlanroom'
  3. any of:
    • any of filter(body.links) where:
      • .href_url.domain.root_domain is not 'reprographix.com'
    • any of body.links where:
      • ml.link_analysis(.).credphish.disposition is 'phishing'
  4. not:
    • all of:
      • sender.email.domain.root_domain is 'reprographix.com'
      • headers.auth_summary.dmarc.pass

Inspects: body.current_thread.text, body.links, body.links[].display_text, headers.auth_summary.dmarc.pass, sender.email.domain.root_domain, type.inbound. Sensors: ml.link_analysis, strings.contains, strings.icontains.

Indicators matched (3)

FieldMatchValue
strings.icontainssubstringPurdue ePlanroom
strings.containssubstringReview This Project
sender.email.domain.root_domainequalsreprographix.com