Medium Severity
Callback Phishing in body or attachment (untrusted sender)
Description
Detects callback scams by analyzing text within images of receipts or invoices from untrusted senders.
References
No references.
Sublime Security
Created Aug 17th, 2023 • Last updated Nov 5th, 2024
Feed Source
Sublime Core Feed
Source
type.inbound
and length(attachments) < 5
and (
any(attachments,
(.file_type in $file_types_images or .file_type == "pdf")
and (
any(ml.nlu_classifier(beta.ocr(.).text).intents,
.name == "callback_scam" and .confidence in ("medium", "high")
)
or any(file.explode(.),
// exclude images taken with mobile cameras and screenshots from android
not any(.scan.exiftool.fields,
.key == "Model"
or (
.key == "Software"
and strings.starts_with(.value, "Android")
)
or (.key == "UserComment" and .value == "Screenshot")
)
and any(ml.nlu_classifier(.scan.ocr.raw).intents,
.name == "callback_scam"
and .confidence in ("medium", "high")
)
)
)
and (
// negate noreply unless a logo is found in the attachment
(
sender.email.local_part in ("no_reply", "noreply")
and any(ml.logo_detect(.).brands,
.name in ("PayPal", "Norton", "GeekSquad", "Ebay", "McAfee")
)
)
or sender.email.local_part not in ("no_reply", "noreply")
)
)
or any(ml.nlu_classifier(body.current_thread.text).intents,
.name in ("callback_scam")
and .confidence in ("medium", "high")
and length(body.current_thread.text) < 1750
)
)
and not (
any(headers.domains, .domain == "smtp-out.gcp.bigcommerce.net")
and strings.icontains(body.html.raw, "bigcommerce.com")
)
and (
not profile.by_sender().solicited
or (
profile.by_sender().any_messages_malicious_or_spam
and not profile.by_sender().any_false_positives
)
)
// 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
)
Playground
Test against your own EMLs or sample data.