Apple released today a critical OS X Network Time Protocol security update for Yosemite, Mavericks, and Mountain Lion users. The update is highly recommended for all users, as it addresses a critical security issue with the software that provides the Network Time Protocol service on OS X. Apple recommends that users install the update “as soon as possible.”
To grab the security update, launch the Mac App Store. More information about the security content of this update soon.
Update: Apple published the details of this security update.
Available for: OS X Mountain Lion v10.8.5, OS X Mavericks v10.9.5, OS X Yosemite v10.10.1
Impact: A remote attacker may be able to execute arbitrary code
Description: Several issues existed in ntpd that would have allowed an attacker to trigger buffer overflows. These issues were addressed through improved error checking.
To verify the ntpd version, type the following command in Terminal: what /usr/sbin/ntpd. This update includes the following versions:
Mountain Lion: ntp-77.1.1