A California software maker has released a program that quickly recovers login passwords from Macs, even when running Apple's completely overhauled OS X Lion, that have been locked, put into sleep mode, or have FileVault disk encryption turned on.

Passware Kit Forensic v11 works by capturing a Mac's computer memory over FireWire and extracting any login passwords that happen to be stored there. The $995 package takes only a few minutes to work, and can also extract passwords stored on a Mac's keychain.

The program from Mountain View, California-based Passware exploits the peer-to-peer characteristic of the FireWire design, which allows any device connected to read and write to any other connected device. As a result, anything stored in a Mac's memory is accessible. The USB protocol, by contrast, generally doesn't share this bidirectional feature, with the exception of a few high-end implementations, said Rob Graham, a noted penetration tester and CEO of Errata Security.

"Hackers have been doing this for a long time," he said, referring to attacks that exploit the p2p nature of FireWire, PCI, and similar interconnects.

Apple has been slowly removing FireWire connections from some of its laptop Macs, and has recently unveiled a new 10Gbit/s interconnect dubbed Thunderbolt. A press release announcing the new Passware kit makes no mention of Thunderbolt, but Graham, who has recently poked holes in the security of the interconnect, said he wouldn't be surprised if it also exposed login passwords stored in memory.

Mac users can foreclose the threat from forensic software by following a two-step process, according to Mac antivirus provider Intego. First, change the default Mac setting so accounts no longer log in automatically at startup. Intego has step-by-step instructions for doing this here. Then, turn off your Mac when it's not being used instead of locking it or putting it to sleep.

Passware's release on Tuesday came the day after Moscow-based Elcomsoft released what it called an "all-in-one" forensic toolkit for iOS devices. A PDF describing the program, which can be used to extract encrypted data stored on iPhones, is here. ®

This article was updated to correct information about how to prevent the attack.