Detection rules › Sublime MQL
Brand impersonation: Charles Schwab
Impersonation of Charles Schwab & Co
Threat classification
Sublime's own taxonomy (not MITRE ATT&CK).
| Category | Values |
|---|---|
| Attack types | Credential Phishing |
| Tactics and techniques | Impersonation: Brand, Lookalike domain, Social engineering |
Event coverage
| Message attribute |
|---|
| headers.auth_summary |
| sender |
| sender.email |
| type |
Rule body MQL
type.inbound
and (
// display name contains charles schwab
(
strings.ilike(strings.replace_confusables(sender.display_name),
'*charles schwab*'
)
// no spaces
or strings.ilike(strings.replace_confusables(sender.display_name),
'*charlesschwab*'
)
// levenshtein distince similar to schwab
or strings.ilevenshtein(strings.replace_confusables(sender.display_name),
'charles schwab'
) <= 1
// sender domain contains schwab
or strings.ilike(strings.replace_confusables(sender.email.domain.domain),
'*schwab*'
)
)
)
// and the sender is not in org_domains or from charles shwab domains and passes auth
and not (
sender.email.domain.root_domain in $org_domains
or (
(
sender.email.domain.root_domain in (
"schwab.com",
"aboutschwab.com.",
"schwabcorrentesettlement.com", // Schawb v. Corrente, et al. Settlement domain
"schwabmoneywise.com",
"schwabe.com", // law firm with name
"proxyvote.com", // sends shareholder voting information with subject of company name
"boheme-schwabing.de", // steakhouse
"lesschwab.com", // tire sales
"schwab-marketing.com", // German Marketing Agency
"schwaben.ca" // unrelated but similar domain
)
or sender.email.domain.domain in ("schwabebooks.ccsend.com")
)
and headers.auth_summary.dmarc.pass
)
)
// and the sender is not from high trust sender root domains
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
)
and not profile.by_sender().solicited
Detection logic
Scope: inbound message.
Impersonation of Charles Schwab & Co
- inbound message
any of:
- strings.replace_confusables(sender.display_name) matches '*charles schwab*'
- strings.replace_confusables(sender.display_name) matches '*charlesschwab*'
- strings.replace_confusables(sender.display_name) is similar to 'charles schwab'
- strings.replace_confusables(sender.email.domain.domain) matches '*schwab*'
none of:
- sender.email.domain.root_domain in $org_domains
all of:
any of:
- sender.email.domain.root_domain in ('schwab.com', 'aboutschwab.com.', 'schwabcorrentesettlement.com', 'schwabmoneywise.com', 'schwabe.com', 'proxyvote.com', 'boheme-schwabing.de', 'lesschwab.com', 'schwab-marketing.com', 'schwaben.ca')
- sender.email.domain.domain in ('schwabebooks.ccsend.com')
- headers.auth_summary.dmarc.pass
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
not:
- profile.by_sender().solicited
Inspects: headers.auth_summary.dmarc.pass, sender.display_name, sender.email.domain.domain, sender.email.domain.root_domain, type.inbound. Sensors: profile.by_sender, strings.ilevenshtein, strings.ilike, strings.replace_confusables. Reference lists: $high_trust_sender_root_domains, $org_domains.
Indicators matched (15)
| Field | Match | Value |
|---|---|---|
strings.ilike | substring | *charles schwab* |
strings.ilike | substring | *charlesschwab* |
strings.ilevenshtein | fuzzy | charles schwab |
strings.ilike | substring | *schwab* |
sender.email.domain.root_domain | member | schwab.com |
sender.email.domain.root_domain | member | aboutschwab.com. |
sender.email.domain.root_domain | member | schwabcorrentesettlement.com |
sender.email.domain.root_domain | member | schwabmoneywise.com |
sender.email.domain.root_domain | member | schwabe.com |
sender.email.domain.root_domain | member | proxyvote.com |
sender.email.domain.root_domain | member | boheme-schwabing.de |
sender.email.domain.root_domain | member | lesschwab.com |
3 more
sender.email.domain.root_domain | member | schwab-marketing.com |
sender.email.domain.root_domain | member | schwaben.ca |
sender.email.domain.domain | member | schwabebooks.ccsend.com |