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HP Path MTU Discovery DoS Vulnerability

Solution:
The vendor recommends the following action:

Reference ndd manpage (1M), /etc/rc.config.d/nddconf

To ensure that this parameter is set each time the system is booted, add the following lines to /etc/rc.config.d/nddconf
TRANSPORT_NAME[<index>]=ip
NDD_NAME[<index>]=ip_pmtu_strategy
NDD_VALUE[<index>]=1

The value of <index> is an integer from 0 to 99. The first parameter specified in the file should use an <index> of 0, the second an <index> of 1, and so on.

Once these changes have been made, execute the following command:

/usr/bin/ndd -c

This sets all of the options specified in the file /etc/rc.config.d/nddconf.

To verify that the parameter is set correctly, use the following command.
/usr/bin/ndd -get /dev/ip ip_pmtu_strategy

This should report a value of 1.

Another way to change the ip_pmtu_strategy parameter on a running system is to use the following NDD command:

/usr/bin/ndd -set /dev/ip ip_pmtu_strategy 1

This setting will only last until the system is rebooted at which point the value of the parameter will be determined by the default value of 2 or whatever value is set in /etc/rc.config.d/nddconf