According to the Nexus Security Bulletin for March, Google unleashed yesterday the OTA update that comes as part of the Monthly Release process. As usual, the Nexus firmware images are ready to download from the Google Developer website. However, this month the BlackBerry Priv receives the update next to the Nexus devices as well.
The most severe issue that becomes a thing of the past once the update completes is a new vulnerability that could enable remote code execution through multiple methods when processing media files. All in all, the new firmware solves six critical problems, eight labeled as "high severity," and two "moderate" issues.
Unfortunately, older versions like KitKat will not get updated and so will remain vulnerable to the recent Mediaserver-related exploits. While BlackBerry has been very quick to deliver the updates this month, Samsung is expected to do it in about three weeks. We will get back to this month's Android security updates as soon as more Google partners deliver them, so stay tuned.