Preview at WWDC likely in June, followed by September launch.
OS X 10.10.2 Includes Fix for 'Thunderstrike' Hardware Exploit Affecting Macs
To secure against Thunderstrike, Apple had to change the code to not only prevent the Mac's boot ROM from being replaced, but also to prevent it from being rolled back to a state where the attack would be possible again. According to people with access to the latest beta of OS X 10.10.2 who are familiar with Thunderstrike and how it works, that's exactly the deep, layered process that's been completed.Thunderstrike is a serious vulnerability discovered earlier this year by security researcher Trammell Hudson, enabling an attacker to replace a Mac's bootrom with malicious code without a user knowing. Since the malicious code is stored in a low level inaccessible to the user, the problem would remain even if the bootrom was replaced.
The proof-of-concept attack is limited in scope, however, as an attacker would require physical access to the Mac or savvy social engineering skills in order to trick a user into attacking his or her Mac themselves. Apple has already addressed the issue in its latest hardware, including the iMac with Retina 5K Display and new Mac mini.
OS X 10.10.2 has been in pre-release testing for over two months and should be made available to the public in the coming days. The most recent OS X 10.10.2 beta was seeded to developers for testing last Wednesday. In addition to the Thunderstrike fix, the upcoming software update addresses security vulnerabilities exposed by Google's Project Zero security team last week.
According to 9to5Mac, the latest OS X Yosemite release will also add iCloud Drive in Time Machine and resolve issues related to Wi-Fi, VoiceOver and security. In particular, a recently identified glitch causing Spotlight on OS X to expose system information to spammers through remote content loading will reportedly be patched. Safari will also gain improved performance and security.
No public instances of Thunderstrike attacks have yet to be reported.