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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2
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54 views

Ubuntu server seems compromised for a DDOS attack

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 ...
-3
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0answers
47 views

How can I implement DDoS in Cloud Environment [on hold]

I am new to the cloud environment as part of my research work i need to implement a ddos attack in cloud environment and then do a traffic analysis and create a new technique to mitigate the attack in ...
0
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3answers
100 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
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3answers
1k 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 ...
-1
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1answer
52 views

How to prevent ddos and brute-force attack by restricting IP's on Wordpress website

I want to make wp-login.php and/or wp-admin accessible only from one country. If I want wp-login.php access only from USA then my approach from .htaccess is like below <Files wp-login.php> ...
0
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0answers
39 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." ...
0
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1answer
171 views

Strange flood of requests to my web server

About an hour ago, strange requests began showing up in my access logs. They are coming in at a rate of ca. 400 req/s and appear to come from IPs all over the place. It started out at a lover rate and ...
-1
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1answer
59 views

Why do I target the proxy server if I send a DDoS attack from it?

I once read that if I send a DDoS attack via a proxy (for example with LOIC), I won't target the server I am trying to send a DDoS attack to but I will actually DDoS the proxy server. Most important ...
2
votes
2answers
127 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 ...
0
votes
1answer
59 views

Identifying attacks by network activity

Is it posible (and how) to tell from a network dump if there is a buffer overflow attack, DoS or brute force attack? A DDoS would be more obvious to identify, but those attacks mentioned above I think ...
0
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0answers
30 views

DOS attack to increase packets received from a single request?

Is there any attack out there that can be implemented where a single request to a server i host for example responds by sending the same file say 20 times back ? the idea behind the attack is to DOS ...
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3answers
127 views

How to identify if my site is vulnerable to DOS/DDOS attacks? [closed]

I am hosting a site on a hosting server. How to identify whether my site is vulnerable to DOS/DDOS attacks?
3
votes
1answer
427 views

Are voluntary / manual DDoS illegal?

Since DDoS is simply a group of subjects coming together to send requests to a particular server, is it true to say that a voluntary DDoS is perfectly valid and legal in US? By that, I mean that a ...
2
votes
2answers
114 views

Will a DDOS attack prevent outbound traffic?

Imagine a scenario where there is a DDOS attack against a target - clients would be unable to connect to the target, but I would like to know if the target could initiate a connection to the outside, ...
0
votes
2answers
694 views

A DDOS attack by uploading a few hundred large files - whats stopping anybody?

I am new to the IT Security field and am essentially a developer as opposed to a networking person hence the question may be a dumb one I am writing a REST service exposed to the internet which ...
0
votes
1answer
158 views

API Key DDOS prevention method

Hi I just wanted some feedback on a DDOS preventing php script that I'm designing. It quite simple and I wanted some feedback on whether you guys think it would be effective. I'm currently using the ...
0
votes
1answer
99 views

what type of attack does LOIC do? [closed]

I have used LOIC (Low Orbit Ion Cannon) earlier . Today i was reading on wikipedia that there are many types of dos attacks , namely SYN attacks , HTTP flooding ,UDP flooding ,etc and two questions ...
0
votes
2answers
92 views

Solution for traffic capturing from router

i'm a newbie and i'm having a problem that i can't find it by google. I'm researching abbout DDoS detecting method now. As we can see that nowadays people often analyze networking traffic from router ...
1
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6answers
368 views

DDOS slow-http attack prevention

I am often getting DDOS attack from multiple IPs with simple HEAD requests. There are around 30 unique IPs creating such attacks. 201.230.167.68 - [05/Jan/2014:00:19:19 +0530] "HEAD / HTTP/1.1" 301 ...
2
votes
2answers
919 views

Outbound DDOS attack from a centos server

We run a mail server (postfix/dovecot/centos 6.4). The hardware is based on a supermicro chasis with IPMI features. It also runs a web interface for accesisng mails(Apache web server ) Recently our ...
1
vote
1answer
92 views

Root/Naked domain and DDOS

Some services like Github has DDOS mitigation measures for their root/naked domain, but not other subdomain(s). What so special about the root domain concerning the DDOS attacks? [1] ...
1
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0answers
236 views

Akamai or Incapsula (or other) for CDN with DDoS Protection? [closed]

One of our clients is launching a new site and I've been tasked with making a short overview of the advantages/disadvantages of Akamai, Incapsula or other CDN providers who are strong with DDoS ...
4
votes
2answers
2k views

My server is used for DDoS attacks

I have webserver (centos + cpanel), and one of the clients used my server for DDoS-ing, how can I identify that client/user? What logs should I look to, is there any settings I can modify so such ...
11
votes
2answers
2k views

How to test against DDoS in a controlled enviroment?

Can you suggest me methods or tools that can help in simulating a DDoS attack in a controlled enviroment (like my private lab)?
6
votes
5answers
1k views

I have a client that is worried about DDOS attacks on their site, and they want penetration testing. Will that help?

My client wants to look into hiring a third party to perform penetration tests on the website that we're developing for them. The website is just a simple 3-month contest site where people can upload ...
16
votes
5answers
14k views

How to simulate DDoS attacks from the Internet?

The idea behind security tests is easy. You want to know what a hacker can do - you hire a security expert who acts like a hacker to see how far he can get. You want to know what an evil admin can do ...
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2answers
182 views

How to avoid DDOS against Kerberos Authentication Server

I have a school project where i am supposed to implement a Kerberos based infrastructure (AS, TGS and resource server). It is already done and working, but i started thinking about how to protect the ...
15
votes
3answers
1k views

NTP DDoS Attack on Home Servers

After some half-good script kiddies found out about this exploit or DDoS method, they have been doing it like crazy to websites, game servers, and now my home servers which allows me to work on some ...
3
votes
2answers
540 views

Blocking incoming traffic from privileged port (< 1024) to mitigate DNS DDos Amplification attacks

Hope someone can clarify. As I understand, in a DNS DDos Amplification attacks Multiple DNS queries are sent to a vulnerable name server with the source IP spoofed to that of the target server. The ...
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votes
1answer
699 views

Linux tools to choose suitable Cisco ASA 5500

I have a linux webhosting server which affects a high DDOS. I want to use Cisco ASA 5500 Series Adaptive Security Appliances to protect the linux server from this DDOS. I know there are many factors ...
1
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3answers
357 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.
2
votes
1answer
268 views

Lots of failed outgoing sshd attempts. Am I hacked?

For the last two days I've been seeing lots of lines in my /var/log/auth.log that look like: sshd[xxxxx]: error: connect_to 0.gravatar.com port 80: failed sshd[xxxxx]: error: connect_to ...
1
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3answers
404 views

Strange Apache access logs

A site of ours has been targeted by some kind of strange attack and I am trying to work out exactly how it has happening. Basically, the strangest thing is that the logs seem to correspond to entirely ...
2
votes
0answers
144 views

DoS stress test not working [closed]

First off I'd like to say this is my first post on StackExchange, so please let me know if there's anything wrong with it. Also, I don't know much about networking and I'm just making a simple java ...
1
vote
1answer
81 views

DNS zone size overload?

Is it possible to DOS DNS by creating custom dns zones with lots of text records in them so that the size of the DNS zone is in the order for example 100 Gigabyes, and then query all the dns records ...
0
votes
1answer
118 views

What packet parameters should be checked to detect layer-7 DDoS attack?

What packet parameters should be checked to detect layer-7 DDoS attack (http flood, slow http request etc.)? Do window size and packet timeline show enough information to detect attack traffic from ...
0
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3answers
395 views

Can one use IP-spoofing to anonymize DDOS attacks?

Since it is possible to fake the source-ip of an ip-package, is it also possible to anonymize DDOS-attacks?
6
votes
4answers
778 views

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
114 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
81 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?
5
votes
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 ...
1
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1answer
874 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, ...
5
votes
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 ...
2
votes
3answers
757 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, ...
0
votes
2answers
317 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 ...
1
vote
2answers
1k 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
votes
1answer
790 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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votes
1answer
210 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
votes
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, ...
1
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1answer
225 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 ...