I looked into it, and the fix is scheduled to be in a future iDRAC update for the R740. I don't like to give ETAs because update releases tend to be very fluid. The current revision and ETA is 3.30 and four months. The revision number and release time will likely change before it is finally released.
 Hello. We have a PowerEdge R740 server with the lastest version of BIOS and iDRAC firmware. BIOS Version 1.4.9iDRAC Firmware Version 3.21.21.21 Openvas find a CSS vulnerability in the url [URL] What this url is for? How I can disable it?  
Openvas detected a vulnerability in iDRAC9