This document provides information about different types of denial of service (DoS) and distributed denial of service (DDoS) attacks, including buffer overflow, ping of death, smurf attack, and TCP SYN attack. It explains that DoS attacks aim to make machines or network resources unavailable by overwhelming them with more requests than their capacity allows. DDoS attacks perform the same type of flooding from multiple sources rather than a single source. The document also discusses how buffer overflows can corrupt data and crash systems, how ping of death exploits IP fragmentation, and how smurf attacks work by amplifying traffic volume through IP broadcast replies.

1. Disclaimer: This tutorial is for educational purposes only and is
not intended to be put into practise unless you have authorised
access to the system you are trying to break into)

2. Denial of service or distributed denial service
of service attack is an attempt to make a
machine or network resource unavailable to
its intended users.
Basically sending more requests than a
capacity of web server. apache or IIS

3. Its simple
When the attack is performed from one source
to one destination its DOS attack
&
When attack is performed from multiple
source to one Destination its DDOS

4. ● Buffer overflow :- name it self clear the
thing :)
● Ping of death :- ping request larger than
65536 byte
● Smurf attack :- A security breach for
flooding
● TCP SYN Attack :- really easy to understand
and interesting

5. Buffers can only hold specific amount of data,
when that capacity has been reached data has
to flow somewhere else,typically into another
buffer which can corrupt the data that already
contained in a buffer

6. A type of DoS attack in which the attacker sends
a ping request that is larger than 65,536 bytes,
which is the maximum size that IP allows. While a
ping larger than 65,536 bytes is too large to fit in
one packet that can be transmitted, TCP/IP
allows a packet to be fragmented, essentially
splitting the packet into smaller segments that
are eventually reassembled.

7. Attacks took advantage of this flaw by
fragmenting packets that when received
would total more than the allowed number of
bytes and would effectively cause a buffer
overload on the operating system at the
receiving end, crashing the system.

8. Smurf attack
From Wikipedia, the free encyclopedia
The Smurf Attack is a distributed denial-of-service attack in which large numbers of Internet
Control Message Protocol (ICMP) packets with the intended victim's spoofed source IP are
broadcast to a coputer network using an IP Broadcast address. Most devices on a network will,
by default, respond to this by sending a reply to the source IP address. If the number of
machines on the network that receive and respond to these packets is very large, the victim's
computer will be flooded with traffic. This can slow down the victim's computer to the point
where it becomes impossible to work on.

9. This is really easy to understand,this attack
send the syn packet to server then wait for
syn/ack from server once it got syn/ack it
keeps server waiting for ack, This creates a
DOS or DDOS to server.

10. ATTACKER
WEB-Server
SYN
SYN/ACK

11. In next Lecture we will cover the following
points
● Prerequisite to DOS tools
● performing DOS Attacks
● AB(apache benchmark)
● Httperf
● slowhttptest
● Golden eye

12. @S3curityB3ast
https://www.breakthesec.com
https://www.youtube.com/user/hackerkaustu
bh