Low Severity

Link: Direct link to Dropbox Paper file

Labels

Credential Phishing
Free file host
Social engineering
Out of band pivot
URL analysis

Description

Detects inbound messages containing links to Dropbox Paper documents using the /scl/fi/ sharing path with a .paper file extension and an rlkey query parameter. This pattern is commonly abused to host phishing content or malicious redirects behind Dropbox's trusted domain, allowing messages to bypass reputation-based filtering while luring recipients into opening a shared document.

References

No references.

Sublime Security
Created Aug 17th, 2026 • Last updated Aug 17th, 2026
Feed Source
Sublime Core Feed
Source
GitHub
type.inbound
and any(body.current_thread.links,
        .href_url.domain.root_domain == "dropbox.com"
        and strings.istarts_with(.href_url.path, '/scl/fi/')
        and strings.iends_with(.href_url.path, '.paper')
        and 'rlkey' in keys(.href_url.query_params_decoded)
)
MQL Rule Console
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