According to Kaspersky Lab, the vulnerability has being exploited by the BlackOasis threat actor. The recent attacks leveraging today's zero-day sent malicious Office documents to victims, which came with an embedded ActiveX object that contained the Flash CVE-2017-11292 exploit.
Vulnerable component: Adobe Flash Player
CVSSv3 score: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE-ID: CWE-704 - Incorrect Type Conversion or Cast (Type Conversion)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a type confusion error when processing .swf files. A remote unauthenticated attacker can create a specially crafted .swf file, trick the victim into opening it and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Note: this vulnerability is being actively exploited in the wild.