Microsoft has released a set of security patches for Windows components in an "out-of-band" release. This means they felt it was important enough to release these fixes now, rather than wait until the next regularly scheduled Patch Tuesday in August.

See the news at cnet and the updated July Security Bulletin at Microsoft for all the gory details.

Note that the new exploit is in Internet Explorer (6, 7, & 8) so IE users should jump on this quickly. However, since IE is part of Windows, everyone is affected and should apply these patches ASAP.