Netatalk is a kernel level implementation of the AppleTalk Protocol Suite, which allows Unix hosts to act as file, print, and time servers for Apple computers. It includes several script utilities, including etc2ps.sh.
The etc2ps.sh script creates temporary files in world-writeable directories with predictable names.
A local attacker could create symbolic links in the temporary files directory, pointing to a valid file somewhere on the filesystem. When etc2ps.sh is executed, this would result in the file being overwritten with the rights of the user running the utility, which could be the root user.
There is no known workaround at this time.
All Netatalk users should upgrade to the latest version:
# emerge sync
# emerge -pv ">=net-fs/netatalk-1.6.4-r1"
# emerge ">=net-fs/netatalk-1.6.4-r1"