Due to a security flaw discovered in its Flash Player software, Adobe released an update to the web plugin earlier this week. Today Apple confirmed that it had updated its plugin blacklist for OS X to stop the system from using a version of Flash Player older than 184.108.40.206 (or 220.127.116.11 on older systems).
According to Apple’s product security team:
Due to security issues in older versions, Apple has updated the web plug-in blocking mechanism to disable all versions prior to Flash Player 18.104.22.168 and 22.214.171.124.
According to Adobe, the vulnerability could allow malicious users to take control of a computer running affected versions of Flash Player. The block only affects Safari, not third-party browsers, so users running outdated versions of Flash Player in other browsers will need to manually update.