dhcpcd is a standards compliant DHCP client daemon. It requests an IP address and other information from the DHCP server, automatically configures the network interface, and tries to renew the lease time.
infamous42md discovered that dhcpcd can be tricked to read past the end of the supplied DHCP buffer. As a result, this might lead to a crash of the daemon.
With a malicious DHCP server an attacker could cause a Denial of Service by crashing the DHCP client.
There is no known workaround at this time.
All dhcpcd users should upgrade to the latest available version:
# emerge --sync # emerge --ask --oneshot --verbose ">=net-misc/dhcpcd-1.3.22_p4-r11"