Distributed Denial Of Service (DDOS) is the intentional paralyzing of a computer network by flooding it with data sent simultaneously from many individual computers (so-called zombies) which are used to stage DDOS attacks

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27
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10answers
23k views

DDoS - Impossible to stop?

Is it possible - in theory - to stop1 a DDoS attack of any size? Many people claim it's impossible to stop DDoS attacks and tell me I just shouldn't mess with the wrong people on the internet. But ...
-2
votes
0answers
38 views

Monitor incoming/outgoing network activity

How can I monitor all the incoming and outgoing packet traffic on my home network? I am looking to see when I am getting DDoSed where the attacks are coming from. I am also looking to make sure my ...
2
votes
2answers
178 views

If I send 4mbps of data to a friend with 4mbps connection, will I DDoS him?

Suppose my friend has a connection of 4mbps. If I just send him 4mpbs of random data with my server, wouldn't it block his connection? Even if the router has firewalls and closed ports, isn't enough ...
0
votes
1answer
43 views

Hosting multiple websites on the same server - Prevention from DoS

I have an server which contains around 4 instances hosted on it. I am aware that if a DoS attack happens on one of the instances it will take down all the other instances too. How to prevent such a ...
0
votes
2answers
37 views

Udp ddos prevention

Okay,if i wanted to prevent a udp flood are these 2 solutions sufficient: -Say that i have only one port open like port 80 however i never use udp interactions what if i blocked the udp port leaving ...
0
votes
1answer
33 views

rate limiting and access filter for web application

I had a requirement of rate limiting and dynamically access controlling access to web application dynamically I want to be able to rate limit access turned on / off dynamically black/white list ...
7
votes
3answers
4k views

Why is it so hard to trace origins of DDOS attacks?

According to the July 2009 cyber attacks Wikipedia article, US & South Korean governments suffered a DDOS attack on their websites. However, up till now they have not been able to find any ...
0
votes
2answers
83 views

Under constant ddos, even after switching 3 differnet routers? [closed]

I started getting ddosed when i pissed some minecraft nerd offt on some twitch chat, which he got banned from, and i never saw him again, but i moved to a hotel for about a week, and i kept getting ...
1
vote
2answers
70 views

Mitigating DDoS With Command of Ports

Is there any type of DDoS where closing or taking full control of all port capabilities would be useful in mitigation of an attack?
-1
votes
1answer
52 views

Azure Based DDOS Mitigation, Azure Based Firewall?

I'd like to mitigate DDOS attacks, for an Azure vm server (just TCP ports 80 and 443). Azure appears to be a great solution. I can't find any Azure documentation, as to if there is an Azure ...
2
votes
1answer
59 views

Do the firewall hardware specifications have to be better than the network it protects?

If I need a bodyguard I'll have to hire someone whose muscles are much tougher than mine. If a server can't handle a DoS/DDoS attack because it consumes it's resources does this mean the firewall has ...
0
votes
0answers
92 views

Is there any method to prevent/trace ddos attack?

I have a debian linux server which run a few online game services. I have some competitors in this area and i think one of them is behind the ddos attacks. I have full access to the router, so I set ...
44
votes
6answers
15k views

What techniques do advanced firewalls use to protect againt DoS/DDoS?

It is hard to protect a server against Denial of Service attacks, DoS/DDoS. The two simple ways I can think of is to use a server with much resources (e.g. CPU and memory), and to build the server ...
5
votes
3answers
405 views

DoS by consuming all hosting trafic

Given a small website hosted on a small data plan, is it possible for someone to keep doing requesting for my website URL or just an image hosted on my website that will consume all my permitted ...
-1
votes
1answer
44 views

Mitigate DDos on Windows box

I would love to know, If you know some way to mitigate DDos/Dos attacks on Windows. In Linux we can Mitigate using the IPTables Almighty, but I wonder If there is something like that in Windows. ...
0
votes
3answers
77 views

Theoretical game server DDoS prevention question

I may not understand how DDoS attacks work at this point, but Im just wondering if this would work for a game server? IF each time a new connection is attempted and the packet or connection type is ...
0
votes
1answer
94 views

What's the typical approach to caching invalid authentication attempts?

Clients (actually software pieces developed by some random dudes all over the Internet) are authenticating on a web server using "basic" authentication scheme and to do so they are passing the ...
0
votes
3answers
118 views

How does blacklisting an IP using a firewall protect against DDoS attacks?

I just read that to protecting a server against a DDoS attack involves blacklisting IP addresses. What does the term blacklisting mean? What does it mean for a firewall to drop a connection? How ...
2
votes
3answers
16k views

Stopping DDOS TCP SYN and UDP flood attacks

I would like to know if it's possible to stop a TCP SYN OR ICMP Flood attacks if these attacks are detected at time. What is the most accurate process to filter these addresses if the only way is to ...
0
votes
1answer
43 views

What are features of a suitable tool for tracking and reporting security incidents? [closed]

What are features of a suitable tool for tracking and reporting security incidents? Is it a bad idea to have one central repository for tracking all types of incidents, from helpdesk issues, to ...
1
vote
3answers
1k views

How to send GET/POST requests without header and agent information

I want to test our DOS prevention system against http requests that are not have header and agent information. Is there any tool I can do that. I tried siege with this command siege -c 3 -b -H ...
-1
votes
2answers
89 views

Is constantly downloading large amount of files from a web server considered DDoS?

For example, there's like a million files stored on a website (publicly, anyone with a link can get it), and I wrote a program to retrieve it one by one. Since obviously my program pings the server ...
5
votes
6answers
6k views

Why can we not block DNS Amplification attack by blocking UDP packets or DNS response packet?

I mean if the attacker tries to ask all the open DNS resolver respond to a web server. The web server can just block its UDP ports. If the all the DNS response go to a Authoritative ...
8
votes
5answers
11k views

How to trace a DDOS attack on a dedicated server and block it?

I have a dedicated server and I'm hosting a game, and the web page (using Apache) for account registering. The server is being ddosed since 8 months ago till today. I've tried to talk with the server ...
0
votes
1answer
59 views

Ongoing DDoS: What is the next step after being able to handle it?

Our websites have been the target of an increasing DDoS, the reason is unknown. Right now, we have taken enough precautions to reliably identify and filter the problematic requests (approx 1 mio/day ...
2
votes
1answer
136 views

What is this attacker trying to accomplish?

My client is who is running a recent version of vBulletin is getting lots strange activity and I'm at a loss to explain what the attacker is trying to accomplish. The attacker registers a fake user ...
22
votes
3answers
3k views

Since I can set the source IP address to anything using raw sockets, does this mean I am untraceable?

For homework, I coded a TCP packet with raw sockets. So I was also able to change the source IP address to whatever I wanted. So why can't someone just make a program, which sends millions of these ...
87
votes
13answers
27k views

Why is it difficult to catch “Anonymous” or “Lulzsec” (groups)?

I'm not security literate, and if I was, I probably wouldn't be asking this question. As a regular tech news follower, I'm really surprised by the outrage of Anonymous (hacker group), but as a ...
0
votes
0answers
63 views

Blocking IP After multiple connection with Netsh advfirewall to mitigate DDos

Hello I wanna block Ip address if they exceed 20 connections with port 80 TCP for HTTP Server. I wanna do this using Netsh advfirewall, In Linux I use IPTables: iptables -I INPUT -p tcp --dport ...
0
votes
2answers
257 views

Am I allowed to DDOS my own server?

I have bought a server and used it to host some game servers or my website. Now I am visiting a computer secruity course and I would like to test some of the presented attacks. Am I allowed to for ...
-6
votes
1answer
114 views

How to avoid DDoS Attack [closed]

I buy my train ticket from our railway local web site. When ticket open for sale on web site then web site original traffic remain 50 (Just an example). Our railway web site is attacked by DDoS for ...
2
votes
3answers
2k views

Why is it easy to detect network layer DDoS attacks?

I have seen numerous research papers that claim it is "easy to detect network layer DDoS attacks" without saying why. Usually these research papers focus on detection or prevention of application ...
42
votes
5answers
8k views

How do major sites prevent DDoS? [duplicate]

As far as I know, I have never heard of or seen any large scale web sites like Amazon, Microsoft, Apple, Google, or Ebay ever suffer from DDoS. Have you? I have a personal philosophy that the bigger ...
1
vote
3answers
736 views

Can anyone DDOS my server with jmeter? Do they need a powerful server for that?

Is there a way to DDOS my web app through jMeter? Can anyone DDOS with a simple PC? I couldn't find any answer here. I would appreciate if anyone could help me out.
5
votes
2answers
789 views

How could a SYN flood affect a home router

I was curious how a DoS attack would affect a home router. In particular, I'm interested in how a SYN flood would affect a home router. The reason I'm interested is due to a Cisco document I read. ...
2
votes
1answer
71 views

Downloading operating systems vulnerable to TCP amplification

I am doing a security research project on TCP amplification, and was looking to download vulnerable OS's for testing. From what I have researched mostly ancient linux kernels (2.0.x and below) and ...
1
vote
2answers
37 views

unprivileged or privileged malware for botnets

For those malwares which are used to organize botnets to DDOS a website, they just need to send and receive HTTP packets. Do they need to be privileged? If they dont need to be privileged, is it true ...
3
votes
2answers
156 views

How web application firewalls protect application from DDoS attacks?

How to protect a web application from DDoS by the implementation of Web Application firewalls? How effective is this method?
0
votes
1answer
133 views

defend against LOIC Hive Mind attack

Other than client puzzles, what are some things a website can do to defend itself against a LOIC Hive Mind attack? The Low Orbit Ion Cannon (LOIC) is an attack tool which features a user-friendly GUI ...
0
votes
1answer
85 views

distinguish between bots and legitimate clients [closed]

If an attack (DoS & DDoS) involves thousands of bots, how can the server distinguish them from legitimate clients?
-1
votes
1answer
108 views

Can the attacker launch a sufficiently large SYN flood to overwhelm the victim's server?

Suppose that the victim's web server infrastructure can process 200,000 TCP connection requests per second. Assume that a single connection request (TCP initial SYN) requires 40 bytes to transmit. The ...
14
votes
7answers
33k views

How do I know if my computer is being used for a botnet-based DDoS attack?

A botnet is a collection of compromised computers, each of which is known as a 'bot', connected to the Internet. When a computer is compromised by an attacker, there is often code within the ...
2
votes
3answers
173 views

Distributed Denial Of Service Attack Mitigation

Is there any way in which you can stop a DDoS attack(or any measure that you can take), if the packets sent by the attacker look like normal traffic? I got the question on an interview (how would you ...
2
votes
4answers
1k views

How to detect bots clicking a link?

I own a url shortening service. I want to deliver only legitimate statistics to my clients. There are possible scenarios that a particular user writes a script to automatically open the shortened URL, ...
2
votes
0answers
274 views

cisco asa syn flood detection and response not working

I have a Cisco ASA 5510 (ASA Version 8.3(2)) that has been getting a syn flood attack on it (or more accurately through it - targeting a host behind it) a couple of times a day for the past few days. ...
4
votes
1answer
378 views

How does a Distributed Denial Of Service Attack work

Let's assume that a hacker has already infected an X number of PCs , each one of them is online. How will he actually perform this attack? Just send ping requests or use his very precious tool to do ...
2
votes
3answers
118 views

Is opening a new mysql connection for each query potentially unsafe?

I am doing some unit testing and noticed that if I click (or have multiple people clicking) the same filter very very fast (very precise I know;) eventually I get a "The connection is already open." ...
2
votes
0answers
67 views

Ubuntu server seems compromised for a DDOS attack [duplicate]

So i have this VPS Ubuntu v12.04 Server running with DigitalOcean. Zpanel/Apache/PHP stack was installed on the Server For the past few days it was occasionally down. Initially, I didn't know what ...
0
votes
3answers
122 views

Questions about ddosing?

Suppose a website is hit by a 500 Mbps DDos, and then the DDos stops for a second or so; does the website recuperate?
6
votes
3answers
3k views

Can someone launch a DOS attack on my IP

Suppose, I have a static IP on my PC and is known to others. None of my softwares listen for remote connection. Is it still possible for someone to DOS attack me in such cases? If yes, how it is ...