tcp sequence number

[tcp sequence numbers co]

I'm looking for parameter settings to setup tcp secquence numbers to help eliminate remote session hijacking attacks (HP 11.x).

[Michael Steele_2]

Hi

Are you referring to port assignments? SWAG

http://www.ingate.com/files/422/fwmanual-en/xa10285.html#AEN10291

[Bill Hassell · Accepted solution]

To see the current setting:

ndd -get /dev/tcp tcp_isn_passphrase

If it reports 0 (zero) then random sequence numnbers are not enabled). You set the value in two places:

At the command line:

ndd -set /dev/tcp tcp_isn_passphrase 1

which is temporary. Permanently set the value by editing /etc/rc.config.d/nddconf:

# Enable random tcp sequences numbers
TRANSPORT_NAME[1]=tcp
NDD_NAME[1]=tcp_isn_passphrase
NDD_VALUE[1]=1

The [1] refers to array entries -- pick an unused entry.