Adobe Flash Player 21.0.0.226 and earlier allows remote attackers to execute arbitrary code via unspecified vectors, as exploited in the wild in May 2016.
https://www.exploit-db.com/exploits/46339/
https://security.gentoo.org/glsa/201606-08
https://helpx.adobe.com/security/products/flash-player/apsb16-15.html
https://helpx.adobe.com/security/products/flash-player/apsa16-02.html
http://www.securitytracker.com/id/1035826
http://www.securityfocus.com/bid/90505
http://rhn.redhat.com/errata/RHSA-2016-1079.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00047.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00046.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00045.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00044.html