Similarly to NTP, the Character Generator Protocol (CHARGEN) is an oldie whose emergence dates back to the 1980s. In spite of this, it is still being used on some connected devices such as printers and photocopiers. The attack comes down to sending tiny packets containing a victim server’s fabricated IP to devices with CHARGEN protocol enabled. In response, the Internet-facing devices submit UDP packets to the server, thus flooding it with redundant data.
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