The rule-update feature in Cisco FireSIGHT Management Center (MC) 5.2 through 5.4.0.1 does not verify the X.509 certificate of the support.sourcefire.com SSL server, which allows man-in-the-middle attackers to spoof this server and provide an invalid package, and consequently execute arbitrary code, via a crafted certificate, aka Bug ID CSCuw06444.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.