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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3answers
42 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 ...
0
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1answer
44 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
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1answer
96 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 ...
0
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0answers
24 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
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2answers
132 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 ...
22
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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 ...
-5
votes
1answer
79 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 ...
1
vote
1answer
106 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 ...
39
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5answers
5k 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 ...
0
votes
1answer
73 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 ...
4
votes
2answers
320 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
58 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
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2answers
34 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
105 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?
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1answer
93 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 ...
0
votes
1answer
81 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?
0
votes
1answer
110 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 ...
2
votes
0answers
153 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. ...
2
votes
0answers
65 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 ...
-1
votes
1answer
243 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> ...
2
votes
3answers
97 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." ...
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votes
1answer
122 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 ...
0
votes
3answers
111 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?
2
votes
3answers
161 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
688 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 ...
0
votes
1answer
66 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
33 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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votes
3answers
329 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?
2
votes
2answers
190 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
1answer
253 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
142 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
134 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
vote
1answer
120 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
341 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 ...
6
votes
3answers
2k 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 ...
16
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 ...
1
vote
2answers
225 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 ...
1
vote
3answers
551 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.
3
votes
2answers
1k 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 ...
2
votes
1answer
449 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 ...
2
votes
3answers
767 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
2answers
1k 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 ...
2
votes
0answers
198 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
112 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
141 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 ...
-4
votes
1answer
160 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?
1
vote
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, ...
5
votes
3answers
3k 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 ...
6
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 ...
0
votes
2answers
444 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 ...