The Mail Filtering Service scans incoming mail for spam, phishing, malware and scam messages. Incoming mail passes through the filter gateways before it reaches the mail servers. Users with ETH accounts may choose to reject spam or mark it with the addition of a tag to the message subject line {Spam?}. ETH account users are also provided with a personal allowlist and blocklist.

MailCleaner is a Swiss product which is used by several Swiss universities. The product runs on our mail gateways and is managed by the Informatikdienste.
https://mailcleaner.ethz.ch

Further instructions

IT Knowledge Base: Mail filter