Adobe released a patch for Reader yesterday. I was not able to see that the download site is distributing 9.3.1. But if you do a check for updates after starting reader you should get 9.3.1
As a side note:
Adobe Rushes Out Patch for Critical Vulnerabilities in Reader, Acrobat
Adobe has released updates for all versions and all operating systems of Acrobat and Reader. The updates are meant to address two vulnerabilities.
The first vulnerability is a Flash vulnerability addressed last week, and is necessary because PDFs can host Flash content. The vulnerability could be exploited to subvert the domain sandbox and make unauthorized cross-domain requests. The second is a critical vulnerability that could cause a crash and potentially allow remote code execution.
Users should update to versions 9.3.1 or 8.2.1.
Coincidentally, a 2009 Global Threat Report from ScanSafe shows that in the 4th quarter of 2009 80% of all web-based exploits were malicious PDFs. It’s not surprising that the PDF number is large, but this number is so large it’s hard to believe, especially in as much as Flash exploits were 18%.
But the underlying issue is spot-on: PDFs and Flash are currently the avenue of choice for malware on the web.