webmail[.]user-coinbase[.]support

The domain webmail.user-coinbase.support was observed delivering a brand impersonation campaign targeting Coinbase. Infrastructure analysis shows the domain resolves to IP address 188.114.96.3, which belongs to AS13335 owned by Cloudflare, Inc., and is geolocated in the United States. The SSL certificate presented for the host is issued by Google Trust Services under the WE1 certificate authority, indicating the use of a legitimate certificate chain despite the malicious intent. HTTP requests to the site return a 403 status code, and the page title returned by the web server is "Roundcube Webmail :: Bienvenido a Roundcube Webmail," suggesting the presence of a Roundcube webmail interface, although the content has not been captured for further analysis.

The domain was registered through Cloudflare, Inc., and the hosting provider is identified as Cloudflare, employing HTTP/3 as part of its service stack. VirusTotal scanning recorded three detections out of ninety‑five security vendors, reflecting a modest but notable level of vendor consensus on malicious behavior. The domain appears on a single security blocklist and has been explicitly blocked by the PhishDestroy service. Current operational status is offline, with the site returning HTTP 403 and no active content visible.

Risk assessment classifies the threat as elevated due to the combination of brand impersonation, cryptocurrency‑related scam categorization, and partial vendor detection. Defensive recommendations include adding webmail.user-coinbase.support and its resolved IP 188.114.96.3 to network deny lists, monitoring for any future re‑registration attempts, and ensuring that endpoint protection solutions incorporate the observed vendor detections. Continuous observation of related threat‑intel feeds for new indicators tied to the Coinbase brand is advised.