This Linux kernel vulnerability affects millions of Linux servers and the researchers believe 66% of Android devices. This exploit can be done on any kernel since Linux 3.8 that was released back in 2012.
This exploit is possible due to a reference leak in the keyrings facility and the proof of concept code was able to gain root privileges. The code for gaining root access on affected kernels was released here and is less than 200 lines of code.
About the only good news out of this issue is that local access would be needed for Linux servers. However, in the Android space a malicious app could just as well take advantage of this vulnerability. SMEP/SMAP/SELinux enabled systems though appear safe.
A kernel patch is expected today for fixing this vulnerability, so make sure you update your Linux kernel ASAP. More details by the researchers via Perception-Point.io.