chrony: Symlink vulnerability

Background

chrony is a versatile implementation of the Network Time Protocol (NTP).

Description

It was found that chrony did not check whether its PID file was a symlink.

Impact

A local attacker could perform symlink attack(s) to overwrite arbitrary files with root privileges.

Workaround

There is no known workaround at this time.

Resolution

All chrony users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-misc/chrony-3.5.1"