Detection rules › Sublime MQL

Credential phishing: AWS Lambda URL with recipient targeting

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

Detects messages containing AWS Lambda URLs with the recipient's email address embedded in the fragment, indicating potential abuse of AWS Lambda services for targeted malicious activities.

Threat classification

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

CategoryValues
Attack typesCredential Phishing
Tactics and techniquesFree subdomain host, Social engineering

Event coverage

Rule body MQL

type.inbound
and recipients.to[0].email.domain.sld == sender.email.local_part
and any(body.links,
        strings.icontains(.href_url.domain.domain, "lambda-url")
        and strings.icontains(.href_url.fragment, recipients.to[0].email.email)
)

Detection logic

Scope: inbound message.

Detects messages containing AWS Lambda URLs with the recipient's email address embedded in the fragment, indicating potential abuse of AWS Lambda services for targeted malicious activities.

  1. inbound message
  2. recipients.to[0].email.domain.sld is sender.email.local_part
  3. any of body.links where all hold:
    • .href_url.domain.domain contains 'lambda-url'
    • strings.icontains(.href_url.fragment)

Inspects: body.links, body.links[].href_url.domain.domain, body.links[].href_url.fragment, recipients.to[0].email.domain.sld, recipients.to[0].email.email, sender.email.local_part, type.inbound. Sensors: strings.icontains.

Indicators matched (1)

FieldMatchValue
strings.icontainssubstringlambda-url