A use-after-free vulnerability was discovered in Adobe Flash Player before 28.0.0.161. This vulnerability occurs due to a dangling pointer in the Primetime SDK related to media player handling of listener objects. A successful attack can lead to arbitrary code execution. This was exploited in the wild in January and February 2018.
http://blog.talosintelligence.com/2018/02/group-123-goes-wild.html
https://access.redhat.com/errata/RHSA-2018:0285
https://github.com/InQuest/malware-samples/tree/master/CVE-2018-4878-Adobe-Flash-DRM-UAF-0day
https://github.com/vysec/CVE-2018-4878
https://helpx.adobe.com/security/products/flash-player/apsb18-03.html
https://securingtomorrow.mcafee.com/mcafee-labs/hackers-bypassed-adobe-flash-protection-mechanism/