The high-profile piece of malware that's been estimated to have infected more than 600,000 users of Apple's Mac OS X worldwide, is in considerably fewer machines now, according to a major security firm.
In a blog post today, software maker and security firm Symantec said that there are now fewer than half that number of machines with the infection, and that the number of active infections is on a downward trend.
"This figure has decreased significantly since then and from our sinkhole data, we have estimated that the number of computers infected with this threat in the last 24 hours is in the region of 270,000, down from 380,000," the company said, adding that it will be monitoring infection levels for the next few weeks.
According to Symantec, most of the infections remain in the United States, followed distantly by Canada and the United Kingdom.
Flashback is a form of malware designed to grab passwords and other information from users through their Web browser and other applications. A user typically mistakes it for a legitimate browser plug-in while visiting a malicious Web site. At that point, the software installs code designed to gather personal information and send it back to remote servers. In its most recent incarnations, the software can install itself without user interaction.
Apple yesterday announced plans to offer a removal tool for the malware, though it has not offered an estimated time of release. Previous such security control features have come as standalone software updates, patching Apple's Mac OS. If you're looking for more information on the malware, and how to remove it, be sure to read CNET's FAQ.