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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How is a ddos simulation any different from a real attack?

I asked a question earlier today on serverfault, but found out that there was also a security stack exchange. I had conflicting answers from there. The following is the link: ...
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3answers
121 views

What are some good ways to prevent a malicious visitor from maxing out our customer's API maximum allowed service calls?

We run an API service. We gave our customer a package for max limit of 12000 API calls / day. He reported to us that a user has been on purposely visiting his web page 12,000 times a day in order to ...
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1answer
102 views

Hacking through a firewall [closed]

couldn't you DDOS attack an firewall somehow so that it would shutdown and you could access the computer?
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3answers
2k 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 ...
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1answer
1k views

How to prevent DHCP Starvation attack?

All this while, I assumed that switchport security is enough to prevent DHCP dos attack. If I set it maximum 1, there can be no more mac addresses packets. But, a friend told me that using the tool, ...
6
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3answers
1k views

First steps in preventing DOS attacks

My server is currently being attacked from another server. This is my log: root@my-server:/var/log# tail -f auth.log Feb 19 11:53:08 my-server sshd[3745]: Disconnecting: Too many authentication ...
0
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2answers
411 views

What could be the reason for the high traffic on the local network? [closed]

In our small company we have very high traffic outbound from local network to server which is getting blocked, and slow downs our server respond time. Especially at night. I am not security ...
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2answers
2k views

DDoS — null route everything not approved

Is it possible to create a route on your internet router which routes traffic unknown to null. So you basically dont even let traffic route into your firewall unless its approved? Can this help detour ...
0
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1answer
1k views

What is the difference between SYN cookie, SYN cache, and SYN proxy?

I am trying to understand some techniques regarding SYN flood prevention and there are three terms I couldn't find a clear explanation of. The terms that are confusing me are: SYN Proxy SYN Cache ...
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1answer
222 views

How does IP Spoofing increase the upload speed?

I was talking earlier to a script kiddie and claimed that IP spoofing can increase the upload speed in a DDOS attack?! that does not make any sense to me According to him if your server has an upload ...
5
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5answers
2k views

How does CAPTCHA mitigate DDoS attacks?

This seems like an easy question, but I've failed to find an answer. One of the uses of CAPTCHA is to cope mitigate Denial of Service attacks. Suppose an adversary performs excessive login attempts, ...
22
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3answers
4k views

How do DoS/DDoS work?

In the last days one could frequently read about attacks from anonymous and LulzSec against different platforms like Sony or HBGary etc. Yesterday for example they DDoS'ed soca.gov.uk and jhw.gov.cn. ...
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2answers
3k views

What approach would you choose to defend againt DDoS attacks from Nginx level?

I use Nginx compiled with the Naxsi module to protect against some vulnerabilities (SQL injection and cross-site scripting). Now I need to apply a layer of poor man's DDoS protection at this level. I ...
4
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1answer
894 views

Can you be DDoS'ed even if you are behind a home router with no open ports?

I was wondering if someone can become a victim of a DDoS attack as home user when only his IP is known by the attackers but he is behind a router with no open ports or other known vulnerabilities? ...
0
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2answers
858 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 ...
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2answers
122 views

I don't understand how BIPS got hacked [closed]

http://www.networkworld.com/news/2013/112513-bitcoin-robbery-276352.html In this story we can see BIPS got hacked, but I don't get how it was hacked when it was offline because of the DDoS.
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3answers
14k 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 ...
1
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1answer
339 views

How is DDoS different from DRDoS?

I understand DDoS is a DoS assault from multiple sources, where a coordinated stream of requests is launched against a target. How is DRDoS different?
2
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1answer
629 views

What is Open Resolver Project and how does it solve DNS reflection attacks?

What is Open Resolver Project and how does it give a solution for DNS reflection attack? I also read that Open Resolver Project follows BCP38. What is BCP38?
0
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1answer
2k views

What methods are there of protecting a VPS from DDOS attacks? [duplicate]

I was just wondering what would be the best way to stop a VPS from being attacked, bandwidth would be a problem in this case so methods that reduce the amount of incoming attacks and stop sending ...
6
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4answers
3k views

Block all BotNets and TOR addresses from accessing our site

I've heard that many DOS attacks and general "black hat hacking" attempts occur over the TOR network. Is it possible for me to dynamically block source IP's by their presence in a BotNet or similar ...
1
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1answer
121 views

What types of hacking attacks happen alongside a DOS or DDOS attack? [closed]

I'm trying to find some good material on this topic for a paper I'm trying to write for class. Any and all help is very much appreciated.
2
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3answers
964 views

How to mitigate SSL based DDoS attacks?

as you probably know the problem with SSL based DDoS attacks is, that the traffic cannot be analysed and filtered by a DDoS mitigation service provider such as Prolexic, Akamai, Radware, etc. without ...
0
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4answers
253 views

What can a zombie computer feasibly install and run?

I'm experimenting with a Proof of Work system that tries to force the use of a browser in order to solve the client puzzle. Basically, instead of just handing off the puzzle as hash with a well known ...
0
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1answer
329 views

Preventing DDoS from faked IP address [duplicate]

According to this answer, it's possible to send a network packet with a forged source IP address. So, what methods a server administrator can take to prevent/block a countless requests from faked IP ...
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3answers
18k views

How can I identify open DNS resolvers in my network?

This article highlights how open DNS resolvers are being used to create DDOS attacks across the internet. How can I identify whether any of our DNS servers are open? If I find that we are running ...
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1answer
634 views

Orbit Downloader botnet program removal [solved]

Recently (shortly after midnight on 10/8/2013) I installed and ran Orbit Downloader. After learning that the latest version (4.1.1.8) has a botnet-like module included I immediately stopped the ...
6
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4answers
677 views

Secure authentication: partial client-side key stretching… please review/criticize my idea

I am trying to figure out what would be the 'perfect' authentication system for a website. On one end, we know that simple hashing algorithms can be brute-forced or cracked in other ways. Hence why ...
7
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5answers
10k 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 ...
2
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2answers
156 views

Which IP / Client is being Ddosed?

I currently have some Vps's and shared hosting plans with a few hosting providers. Recently one of my shared hosting accounts was suspended due to a denial of service attack. I understood why they had ...
5
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2answers
1k views

Does a DDoS attack have other purposes beyond a lack of availability? [duplicate]

I'm currently researching DDoS attacks for an article I'm writing and apart from the obvious lack of availability of the target host and their services, is there anything else a DDoS can help ...
22
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7answers
15k 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 ...
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1answer
131 views

What are the hardwares used to protect against a DDoS attack on Network layer

What hardware is used to prevent a DDoS attack on a network layer? This question is for my project which I am doing. I have a game server and I need to simulate an attack - an SYN flood. So what ...
4
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3answers
4k views

How to protect myself against paid DDoS services?

I am domestic user and I am getting attacked regularly by a guy that hates me. Here is the background story: that guy uses Skype resolvers (tools offered by paid DDoS services) to find out my IP ...
4
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6answers
642 views

Bot detecting by considering request inter-arrival time

If there are some chances to detect a bot by considering the users page viewing time, is it possible to measure this time? When a user request for a page (page request), browser request for several ...
0
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1answer
107 views

Finding the method of attack [closed]

My server has been repeatedly attacked in the last few days. Here's the observations: The ISP server traffic monitor shows the incoming traffic goes up to 300Mbps (with no outgoing traffic), and ...
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2answers
105 views

Analysing server (VPS) before hosting a government website [closed]

Hosting a government website would definitely increase reputation, but it would also bring higher chances of the hosting server getting attacked by DDoS attacks. It's a cPanel based VPS. What basic ...
0
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3answers
943 views

SSL vs TLS, which is less vulnerable to DOS attacks?

When I learned TLS does not allow a connection to be created until it is has finished a secure handshake, i figured that would make it better for preventing DoS attacks. However, all I seem to find ...
3
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4answers
4k views

Find out how my server is being used for DDOS attacks

I got an email from Amazon that my Amazon EC2 server is being used for DDoS attacks and they have closed all ports except SSH. This is tragical for me but I have not been able to find out how and ...
5
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5answers
5k 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 ...
3
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3answers
335 views

How similar are bots regarding their HTTP GET request?

Lets assume a botnet is attacking a website by HTTP GET flooding. To find the bots, the only way seems to be finding the similarities of the HTTP GET requests considering the URL and header fields, ...
6
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3answers
536 views

Lessen impact of DoS attack on cpu-expensive login?

This is a follow-up to my previous question: Prevent DOS against RSA authentication. This question is also discusses a similar problem: Prevent denial of service attacks against slow hashing ...
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votes
1answer
368 views

Spoofed DDoS mitigation / DNS amplification mitigation [duplicate]

Recently my server has been attacked multiple times, after looking at my firewall I've come to the conclusion that the IP's are spoofed. (10,000+ IP's connect at once) I'm running Win server 2012 x64 ...
5
votes
1answer
292 views

Are latency based Proof-of-Work systems capable of preventing DDoS attacks on popular hidden tor services (.onion websites)?

I was reading an interesting article found here: http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-703.pdf It's titled "Lazy Susan: dumb waiting as proof of work". It suggested the following in section ...
1
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0answers
334 views

Is anything written in the book “Internet Denial of Service: Attack and Defense Mechanisms” c2004 still valid? [closed]

I was reading through some of this book on google: http://books.google.ca/books?id=qmdCs_Jf2AEC It is uploaded to a hungarian website here: http://denialofservice.uw.hu/index.html I was reading... ...
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1answer
2k views

DoSing my Home Network with only a Public IP address [closed]

+--------------------------------------------------------+ | Client Host Name |.. IP Address ..|.... MAC Address ...| | Desktop-Home ....| 192.168.1.100 | 00:19:D1:EA:03:68 | | GT-S5380K ...
1
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1answer
135 views

Botnet Attempting to Login to Website

Our server has recently become a target of what appears to be a botnet attack. The first indication was an insane amount of traffic to one of our client's websites - so heavy that the server entirely ...
18
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3answers
6k views

DNS Amplification DDOS attack

During the weekend I made some tests to simulate an DNS Amplification DDOS attack. sending about 90Mb/s traffic I was able to generate about x.x Gb/s amplified traffic which sent our datacenter ...
5
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2answers
7k views

How can I detect/withstand DNS amplification attack?

I am a developer, and I am trying to get an insight into what could I do to enable my application to withstand a DNS amplification kind of attacks. Would such prevention methods help against DOS type ...
15
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7answers
1k views

Would it be possible to overload a large part of the internet, and if so then how?

Last week a news article went viral about a Dutch web hosting/data center company that was allegedly using a DNS amplification attack to DDoS an anti-spam company, because they blacklisting the ...