Can F5 restrict the file types transferred via FTP?

If your server is web based you can use ASM to restrict file types
https://my.f5.com/manage/s/article/K78925560

Hi SanYang

You need waf module to restrict the files and if you only have LTM , it cannot restrict any files 

For FTP that doesn't seem normally possible. The FTP profile and the FTP commands in iRule don't give this option.

It is probably possible with looking at the data with an iRule and looking for the file name in the PUT command, but that requires some deep iRule knowledge an own development. If your not already an above average user of that it isn't possible.

This article gives nice info about how to set restrictions to FTP with an iRule:

iRule Security 101 - #07 - FTP Proxy | DevCentral

Below is an iRule that should get you going. You probably also want to check on PUT and MPUT besides STOR.

when RULE_INIT {
  set DEBUG 1
}

when CLIENT_ACCEPTED {
  if { $::DEBUG } { log local0. "client accepted" }
}

when CLIENT_DATA {
  if { $::DEBUG } { log local0. "----------------------------------------------------------" }
  if { $::DEBUG } { log local0. "payload [TCP::payload]" }
  set client_data [string trim [TCP::payload]]
  #---------------------------------------------------
  # Block or alert specific commands
  #---------------------------------------------------
  switch -glob [string tolower $client_data] {
    "stor *.tar" -
    "stor *.gz" -
    "stor *.tgz" -
    "stor *.tar.gz" -
    "stor *.zip" {
      if { $::DEBUG } { log local0. "LOG: STOR request detected" }
      
      TCP::respond "550 STOR filetype not allowed\r\n"
      TCP::payload replace 0 [string length $client_data] ""
      return
    }
  }      
  TCP::release
  TCP::collect
}

when SERVER_CONNECTED {
  if { $::DEBUG } { log "server connected" }
  TCP::release
  TCP::collect
  clientside { TCP::collect }
}
when SERVER_DATA {
  if { $::DEBUG } { log local0. "payload <[TCP::payload]>" }
  TCP::release
  TCP::collect
}

when CLIENT_CLOSED {
  if { $::DEBUG } { log local0. "client closed" }
}

When  using WinSCP, it shows when the upload is being blocked.