Another XDA member named Chainfire has devised a one click root-method using the exploit. Samsung has been notified about the situation and we wouldn't be surprised to find the Korean based manufacturer sending out a patch soon to close this opening.
In the meantime, here is a list of devices that could be affected. Samsung Galaxy S II (GT-I9100), Samsung Galaxy S III (GT-I9300), Samsung Galaxy S III LTE (GT-I9305), Samsung GALAXY Note (GT-N7000), Samsung GALAXY Note II (GT-N7100), Samsung GALAXY Note II Verizon-Locked Bootloader (SCH-I605), Samsung GALAXY Note 10.1 (GT-N8000), Samsung Galaxy Note 10.1 (GT-N8010).
A developer named Supercurio has come up with an instant fix, which needless to say, you use at your own risk. You can find the site, called Project Voodoo, by clicking on this link.
Recently discover a way to obtain root on S3 without ODIN flashing.
The security hole is in kernel, exactly with the device /dev/exynos-mem.
This device is R/W by all users and give access to all physical memory … what’s wrong with Samsung ? […]
The good news is we can easily obtain root on these devices and the bad is there is no control over it.
Ram dump, kernel code injection and others could be possible via app installation from Play Store. It certainly exists many ways to do that but Samsung give an easy way to exploit. This security hole is dangerous and expose phone to malicious apps. Exploitation with native C and JNI could be easily feasible."-alephazin, XDA
source: XDA, TheNextWeb, via AndroidAuthority