Hello everyone. Welcome back to the next section. It is for
intersection will be talking all about the different attack vectors
over the network. What are the different tools
that can be used in order to session?
Hijack? If input called to get started,
we talked about the first attack Vector known as
TCP predicting the sequence. This is an old risk and
not that something that we see on modern day.
As we saw in a previous section bad
we did take a look at the tree behind check
for a TCP connection and
in why shock we did see that by
default. The tool shows us. The
first sequence number to be a zero, but
that is only for human readability.
And when we looked at the actual data itself, it
was quite sure that there was a pseudo-random number
that was generated, and which was
very difficult to protect itself.
So what candidly happen during this attack is
such that if an attacker is able to guess
a particular sequence number that is being generated during
the handshake. Those packets could be forced. And
while doing so based on
the type of attack, the attacker
can actually inject. The data core
can actually send out different TCP
Flags in order to either terminate
the connection as well.
And these sort of and abilities were actually seen in
older OSS such as BSD, Unix
and Windows NT 3.5 and
for as well, there's something we
don't see on modern day to day open
systems because they have ensured that every operating
system can actually generate a random number,
such that an attacker can operate it.
Just let's understand the scenario. So, in a typical scenario where
we have a user actually
trying to create a TCP 3-way handshake. So,
as we know the first packet, that would be sent is the syn
flag, followed by that. The server is
going to respond back with the Synod ack. And in
order to complete the three way. The client is again, going
to send back the acknowledgement work in order to
complete a connection.
So, if we take the scenario, where an attacker is
able to send the
flag such that you can predict the sequence in
such a way, spoofing, the source, as the victim itself.
So the server is going to respond back
to the source. That is the victim of you along
with the particular acknowledge
and flag in response.
And in order to complete the third acknowledgement
flag, the attacker is
again going to print the sequence and computer 3-way
handshake. So this is something good
to know basis as to how this attack has
already happened.
That's it for this video. Thank you.