Detection rules › Sublime MQL

Open redirect: Indeed

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

Detects emails containing links using Indeed '/r?target=xxxxxx' open redirect where the email has not come from indeed.com

Threat classification

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

CategoryValues
Attack typesCredential Phishing, Malware/Ransomware
Tactics and techniquesOpen redirect

Event coverage

Rule body MQL

type.inbound
and (
  (
    sender.email.domain.root_domain != "indeed.com"
    and any(body.links, "indeed_open_redirect" in .href_url.rewrite.encoders)
  )
  or any(attachments,
         .file_type == "pdf"
         and any(file.explode(.),
                 any(.scan.url.urls,
                     "indeed_open_redirect" in .rewrite.encoders
                 )
         )
  )
)

// negate highly trusted sender domains unless they fail DMARC authentication
and (
  (
    sender.email.domain.root_domain in $high_trust_sender_root_domains
    and not headers.auth_summary.dmarc.pass
  )
  or sender.email.domain.root_domain not in $high_trust_sender_root_domains
)

Detection logic

Scope: inbound message.

Detects emails containing links using Indeed '/r?target=xxxxxx' open redirect where the email has not come from indeed.com

  1. inbound message
  2. any of:
    • all of:
      • sender.email.domain.root_domain is not 'indeed.com'
      • any of body.links where:
        • .href_url.rewrite.encoders contains 'indeed_open_redirect'
    • any of attachments where all hold:
      • .file_type is 'pdf'
      • any of file.explode(.) where:
        • any of .scan.url.urls where:
          • .rewrite.encoders contains 'indeed_open_redirect'
  3. any of:
    • all of:
      • sender.email.domain.root_domain in $high_trust_sender_root_domains
      • not:
        • headers.auth_summary.dmarc.pass
    • sender.email.domain.root_domain not in $high_trust_sender_root_domains

Inspects: attachments[].file_type, body.links, body.links[].href_url.rewrite.encoders, headers.auth_summary.dmarc.pass, sender.email.domain.root_domain, type.inbound. Sensors: file.explode. Reference lists: $high_trust_sender_root_domains.

Indicators matched (3)

FieldMatchValue
body.links[].href_url.rewrite.encoderscontainsindeed_open_redirect
attachments[].file_typeequalspdf
file.explode(attachments[])[].scan.url.urls[].rewrite.encoderscontainsindeed_open_redirect