Detection rules › Sublime MQL
Open redirect: embluemail.com
Message contains use of the embluemail.com redirect. This has been exploited in the wild.
Threat classification
Sublime's own taxonomy (not MITRE ATT&CK).
| Category | Values |
|---|---|
| Attack types | Credential Phishing, Malware/Ransomware |
| Tactics and techniques | Open redirect |
Event coverage
Rule body MQL
type.inbound
and any(body.links,
.href_url.domain.domain == "nts.embluemail.com"
and strings.istarts_with(.href_url.path, '/p/cl')
and strings.icontains(.href_url.query_params, '!')
and regex.icontains(.href_url.query_params,
'\!(?:((?:%68|h)(?:%74|t){2}(?:%70|p)(?:%73|s)?)?(?:%3a|:))?(?:%2f|\/){2}'
)
)
and not sender.email.domain.domain == "nts.embluemail.com"
and not strings.iends_with(headers.message_id, '@embluemail.com>')
// 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.
Message contains use of the embluemail.com redirect. This has been exploited in the wild.
- inbound message
any of
body.linkswhere all hold:- .href_url.domain.domain is 'nts.embluemail.com'
- .href_url.path starts with '/p/cl'
- .href_url.query_params contains '!'
- .href_url.query_params matches '\\!(?:((?:%68|h)(?:%74|t){2}(?:%70|p)(?:%73|s)?)?(?:%3a|:))?(?:%2f|\\/){2}'
not:
- sender.email.domain.domain is 'nts.embluemail.com'
not:
- headers.message_id ends with '@embluemail.com>'
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: body.links, body.links[].href_url.domain.domain, body.links[].href_url.path, body.links[].href_url.query_params, headers.auth_summary.dmarc.pass, headers.message_id, sender.email.domain.domain, sender.email.domain.root_domain, type.inbound. Sensors: regex.icontains, strings.icontains, strings.iends_with, strings.istarts_with. Reference lists: $high_trust_sender_root_domains.
Indicators matched (6)
| Field | Match | Value |
|---|---|---|
body.links[].href_url.domain.domain | equals | nts.embluemail.com |
strings.istarts_with | prefix | /p/cl |
strings.icontains | substring | ! |
regex.icontains | regex | \!(?:((?:%68|h)(?:%74|t){2}(?:%70|p)(?:%73|s)?)?(?:%3a|:))?(?:%2f|\/){2} |
sender.email.domain.domain | equals | nts.embluemail.com |
strings.iends_with | suffix | @embluemail.com> |