Detection rules › Sublime MQL

Link: Apple TestFlight from suspicious sender

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

Detects messages containing Apple TestFlight links from free email providers or suspicious senders with no prior benign communication history.

Threat classification

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

CategoryValues
Attack typesCredential Phishing
Tactics and techniquesFree email provider, Evasion

Event coverage

Rule body MQL

type.inbound
and any(body.links,
        .href_url.domain.domain in ('testflight.apple.com')
        or (
          .href_url.domain.root_domain == "mimecastprotect.com"
          and any(.href_url.query_params_decoded['domain'],
                  . in ("testflight.apple.com")
          )
        )
)
and not (
  (subject.is_forward or subject.is_reply)
  and (length(headers.references) != 0 or headers.in_reply_to is not null)
  and length(body.previous_threads) > 0
)
and (
  sender.email.domain.domain in $free_email_providers
  or beta.profile.by_reply_to().solicited == false
  or (
    beta.profile.by_reply_to().any_messages_malicious_or_spam
    and not beta.profile.by_reply_to().any_messages_benign
  )
)

Detection logic

Scope: inbound message.

Detects messages containing Apple TestFlight links from free email providers or suspicious senders with no prior benign communication history.

  1. inbound message
  2. any of body.links where any holds:
    • .href_url.domain.domain in ('testflight.apple.com')
    • all of:
      • .href_url.domain.root_domain is 'mimecastprotect.com'
      • any of .href_url.query_params_decoded['domain'] where:
        • . in ('testflight.apple.com')
  3. not:
    • all of:
      • any of:
        • subject.is_forward
        • subject.is_reply
      • any of:
        • length(headers.references) is not 0
        • headers.in_reply_to is set
      • length(body.previous_threads) > 0
  4. any of:
    • sender.email.domain.domain in $free_email_providers
    • beta.profile.by_reply_to().solicited is False
    • all of:
      • beta.profile.by_reply_to().any_messages_malicious_or_spam
      • not:
        • beta.profile.by_reply_to().any_messages_benign

Inspects: body.links, body.links[].href_url.domain.domain, body.links[].href_url.domain.root_domain, body.links[].href_url.query_params_decoded['domain'], body.previous_threads, headers.in_reply_to, headers.references, sender.email.domain.domain, subject.is_forward, subject.is_reply, type.inbound. Sensors: beta.profile.by_reply_to. Reference lists: $free_email_providers.

Indicators matched (3)

FieldMatchValue
body.links[].href_url.domain.domainmembertestflight.apple.com
body.links[].href_url.domain.root_domainequalsmimecastprotect.com
body.links[].href_url.query_params_decoded['domain'][]membertestflight.apple.com