For the second time in a week, Adobe has issued an emergency update to fix a critical security flaw that crooks are actively exploiting in its Flash Player software. Updates are available for Flash Player on Windows and Mac OS X.

Last week, Adobe released an out-of-band Flash Patch to fix a dangerous bug that attackers were already exploiting. In that advisory, Adobe said it was aware of yet another zero-day flaw that also was being exploited, but that last week’s patch didn’t fix that flaw.

Earlier this week, Adobe began pushing out Flash v. 16.0.0.296 to address the outstanding zero-day flaw. Adobe said users who have enabled auto-update for Flash Player will be receiving the update automatically this week. Alternatively, users can manually update by downloading the latest version from this page.

Adobe said it is working with its distribution partners to make the update available in Google Chrome and Internet Explorer 10 and 11. Google Chrome version 40.0.2214.93 includes this update, and is available now. To check for updates in Chrome, click the stacked three bars to the right of the address bar in Chrome, and look for a listing near the bottom that says “Update Chrome.”

To see which version of Flash you have installed, check this link. Windows users who browse the Web with anything other than Internet Explorer may need to apply this patch twice, once with IE and again using the alternative browser (Firefox, Opera, e.g.).

Tags: 0day, adobe flash player, Flash Player 16.0.0.296, Flash zero day, zero day