Adobe Flash Player 21.0.0.197 and earlier allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via unspecified vectors, as exploited in the wild in April 2016.
https://security.gentoo.org/glsa/201606-08
https://helpx.adobe.com/security/products/flash-player/apsb16-10.html
https://helpx.adobe.com/security/products/flash-player/apsa16-01.html
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-050