Predictable Exact Value from Previous Values vulnerability in Mitsubishi Electric Corporation GOT2000 Series GT21 model versions 01.49.000 and prior and GOT SIMPLE Series GS21 model versions 01.49.000 and prior allows a remote unauthenticated attacker to hijack data connections (session hijacking) or prevent legitimate users from establishing data connections (to cause DoS condition) by guessing the listening port of the data connection on FTP server and connecting to it.

Predictable Exact Value from Previous Values vulnerability in Mitsubishi Electric Corporation GOT2000 Series GT21 model versions 01.49.000 and prior and GOT SIMPLE Series GS21 model versions 01.49.000 and prior allows a remote unauthenticated attacker to hijack data connections (session hijacking) or prevent legitimate users from establishing data connections (to cause DoS condition) by guessing the listening port of the data connection on FTP server and connecting to it.

A denial-of-service and spoofing (session hijacking of data connections) vulnerability exists in the FTP server function on GOT2000 series and GOT SIMPLE series because the port number of a data connection can be easily guessed due to predictable exact value from previous values.