In ground breaking research, dubbed Faxploit, Check Point researchers show how cyber criminals could infiltrate any home or corporate network by exploiting all-in-one printer-fax machines. The vulnerability lies in the fax protocol itself. A fax number is the only thing required to carry out the attack. The only information required to do this is the organization’s fax number something which is often publicly available on any employees business card or company website. The research was carried out on HP fax machines, however the same fax communication protocols are used by other fax machine vendors.”]
Source: https://blog.checkpoint.com/2018/08/12/faxploit-hp-printer-fax-exploit/