Detection rules › Sublime MQL

Open redirect: Avast

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

Detects emails containing links to avast.com leveraging an open redirect

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 any(body.links,
        .href_url.domain.root_domain == "avast.com"
        and strings.contains(.href_url.query_params,
                             "DisplayRedirectCustomPage"
        )
)
and sender.email.domain.root_domain != "avast.com"
and (
  not profile.by_sender().solicited
  or (
    profile.by_sender().any_messages_malicious_or_spam
    and not profile.by_sender().any_messages_benign
  )
)

Detection logic

Scope: inbound message.

Detects emails containing links to avast.com leveraging an open redirect

  1. inbound message
  2. any of body.links where all hold:
    • .href_url.domain.root_domain is 'avast.com'
    • .href_url.query_params contains 'DisplayRedirectCustomPage'
  3. sender.email.domain.root_domain is not 'avast.com'
  4. any of:
    • not:
      • profile.by_sender().solicited
    • all of:
      • profile.by_sender().any_messages_malicious_or_spam
      • not:
        • profile.by_sender().any_messages_benign

Inspects: body.links, body.links[].href_url.domain.root_domain, body.links[].href_url.query_params, sender.email.domain.root_domain, type.inbound. Sensors: profile.by_sender, strings.contains.

Indicators matched (2)

FieldMatchValue
body.links[].href_url.domain.root_domainequalsavast.com
strings.containssubstringDisplayRedirectCustomPage