Denial of Service is a family of attacks that attempt to force a target to use up resources (CPU time, memory, bandwidth etc) through flood a target with useless packets, connections or tasks

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How to perform a proper DDoS test in a safe and controlled way?

What is the proper and safe way to perform a DDoS test without crashing the whole infrastructure? What different types of DDoS attacks are there and what things should be considered performing such a ...
6
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1answer
172 views

What's happening on my wifi? NTP and ACK STORM attacks.

I'm wondering if these attacks are something to worry about, or just my router being a router. [DoS attack: ACK Scan] attack packets in last 20 sec from ip [60.221.254.230], Friday, May 06,2016 21:12:...
0
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0answers
29 views

Stats needed for DOS attack prevention setup

Server - JBoss AS7.1.1 Java 6 Web server - F5 I have a sticky session based load-balanced servers (2 JBoss servers running in different servers) and we have a need to prevent DOS attack. I have ...
2
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1answer
57 views

How can Heap Pollution cause a security flaw

I came across this rule in the CERT Secure Coding Standart for Java. Heap Pollution. I understand this can cause the programm throwing an exception at runtime, but i can't understand how this could ...
0
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1answer
39 views

How do you shun an IP automatically based on the number of current connections?

If I have a single IP that's trying a Denial of Service attack, how can I automatically have it banned/shunned? I go in and manually put it in a group of banned IP addresses, but I'd like for it to ...
3
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1answer
65 views

Do a DoS where you permit only your own connection?

Yesterday I was discussing with my brother, a computer scientist, if it is posible to perform a Denial of Service on a webpage so you block all the traffic to the web but you allow your connection to ...
-1
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1answer
100 views

What anti-DDoS solutions for Windows are there?

I would love to know, If there is a way to mitigate DDos/Dos attacks on Windows. In Linux we can Mitigate using the almighty iptables, but I wonder if there an equivalent for Windows.
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0answers
94 views

Any vulnerability in .net implementation for C# object.GetHashCode?

I've already asked this question on SO, but I think that this forum is more appropriate to discuss security issues. My point is that most OO languages has a way to get a unique hash code for an ...
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0answers
33 views

Preventing denial of email (Gmail)

Case 1: The attacker is or has access to MITM the ISP(3g/2g). The ISP also happens to be the GSM company. This could be because of police supervision. He is forced to use computer with a backdoor. ...
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1answer
82 views

What's a good way to prevent DoS attacks? [duplicate]

Is there a good way to prevent DoS attacks? Because I don't want my site to be taken down from someone requesting an overload amount of information and then the server cannot handle it.
3
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2answers
532 views

Can an attacker slow down my server without compromising it?

We have a Linux server with WHM/cPanel which has been running without problems for almost 3 years now. Yesterday, the server became unresponsive (it was definitely there though) for around an hour. ...
4
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0answers
88 views

Attacks on wifi router, don't know what to do or if I should be concerned [closed]

I'm wondering if these attacks are something to worry about, or just my router being a router. [DoS attack: ACK Scan] attack packets in last 20 sec from ip [60.221.xxx.xxx], Friday, May 06,2016 21:12:...
1
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2answers
70 views

OpenSSH DOS exploit proof of concept [closed]

For some research I'm looking for a working DOS exploit for OpenSSH. The OpenSSH version, vulnerable to the exploit is irrelevant. The only requirement that I have is, that the exploit should work for ...
8
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3answers
13k 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 ...
5
votes
3answers
990 views

Is this a symptom of an attack (DoS/DDoS)?

I work for an e-commerce website in my country and this is the second time we suffer an attack. At least, looks like one. We have a search functionality in our website and the supposed attacker is ...
4
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1answer
1k 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?
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1answer
73 views

Denial of Service during scanning [closed]

As I know you can do Denial of Service when footprinting with scanners, like nmap or Maltego. But is it legal? As I know, scanning isn't illegal but doing DoS attacks is. EDIT I meant if you scan ...
22
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3answers
3k views

New denial-of-service vulnerability in TLS protocol, based on shooting down other users' sessions?

I think I have a new denial-of-service attack on TLS, and I'd like you to check whether this is a real vulnerability. I recently learned about the proper way to drop an authenticated client session (...
1
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1answer
88 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 ...
1
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1answer
130 views

How can one securely hash passwords server side while avoiding DoS?

It is generally recommended that one use a slow hash function to hash passwords. However, does this create a DoS risk?
4
votes
1answer
352 views

Can a Cisco ASA 5505 block this DDoS attack?

Since more than a week ago, my dedicated server (located at ovh.com) has been under TCP SYN (I think) attack. OVH don't care about it but this attack is killing my server with a high CPU load (...
0
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3answers
52 views

Denial of Service by SQL queries - are selective queries better than queries that return a lot?

Lets say I have a search form for a blog (or any other system that would use SQL to run queries) and I want to protect it from denial of service. An attacker wants to attack my site by flooding the ...
0
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0answers
40 views

DDoS Solution for request floods [duplicate]

What are the mitigations to protect from ddos? Is using firewall like cloudflare would help or not? My use case is just want to make sure that no one is sending flood of requests i.e. thousands per ...
2
votes
2answers
80 views

XSS on a single page web application

I'm practicing stored XSS attacks on my vulnerable single page web application. I want to achieve some kind of DoS attack, where the page keeps reloading from the server. I can easily inject window....
2
votes
2answers
54 views

Is my computer getting attacked? [closed]

Would anyone be able to have a look at the pcap from my computer? I am thinking my computer get attacked by a process and keeps sending out packets from my computer to DoS my network. I get errors ...
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2answers
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How long does it take to execute a DoS attack on a PC using the ping… -t CMD command?

Suppose the target of a Denial of Service attack is a PC on LAN with IP 192.168.1.10. Then, I can continue to ping the target by running the ping command in an infinite loop in CMD, that is, by ...
7
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3answers
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nf_conntrack: table full, dropping packet

I see a lot of these messages in /var/log/messages of my Linux server kernel: nf_conntrack: table full, dropping packet. kernel: __ratelimit: 15812 callbacks suppresse while my server is under DoS ...
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votes
1answer
48 views

Is it a kind of DoS attack? [closed]

If an attacker can kick any users(includes web admin) offline (via unspecified vectors), is it a kind of DoS(Denial of Service) attack? My friends think it is obviously the DoS attack , because the ...
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votes
1answer
155 views

What is the most secure database? [closed]

I need to learn about database systems, but first I need to know which is the safest. For example, information like government data need to be protected, so what is the best database to handle this ...
1
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1answer
69 views

How to successfully report DoS attack coming from a big ISP?

A few weeks ago I reported a small botnet which is coming from the network of a big Internet provider. They asked me for more details which I provided. But the attack is going for weeks already and ...
4
votes
2answers
5k views

How to mitigate UDP flood attacks?

My friend linked me some website where you pay $5.00 / m and get access to a plethora of 'dos stresser' tools that offer udp flooding, and other malicious flooders. It's a web-based system and you ...
4
votes
2answers
144 views

Reverse-proxy not a solution to DDOS attacks when hosted on PaaS?

We run our apps on Heroku and use Cloudflare as a CDN and to protect against DOS attacks. However, we recently experienced (a relatively minor) attack that managed to easily bypass Cloudflare by ...
25
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4answers
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Normal usage vs. denial-of-service? How many requests are needed to talk about a denial of service?

Recently I used a tool to download a website and as part of the tool one could adjust the number of parallel connections. So now I found myself asking: starting from how many requests a provider could ...
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0answers
57 views

Can external registrar be DoS'd?

So I have been experimenting with wps-enabled routers lately. I have written a short script with a single purpose: To send a wps pin to the external registrar and then immediately end the request by ...
2
votes
0answers
60 views

Rogue Containment on a wired network (mostly)

I work as a security analyst for a large company. The answer must provide remote support. We are currently looking to build a piece of software (integrating existing products with home grown ...
3
votes
1answer
64 views

If a firewall deletes DOS packets before they reach the designated application. Is it then possible to break trough the firewall with a DDOS attack?

My Question is that if a Firewall blocks for example a DOS attack of UDP packets. Is it then possible to "break" or take up the capacity of a server by sending enough packets trough a DDOS attack? or ...
4
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1answer
62 views

Security monitoring in the cloud?

I am working for a company which works with PHI, HIPAA, PCI and other highest sensitivity data. Their current security architecture uses hardware network monitoring tools to monitor the network ...
8
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2answers
4k views

Anti-DoS WebSockets Best Practices

What are the best practices for thwarting DoS attacks for a WebSocket server? Is there a comprehensive site or document that can be referenced?
10
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3answers
2k views

Is there any way to stop DDOS attacks? [duplicate]

As many other webmaster I am facing problems with DDOS attacks. I have tried denying offending IP addresses from htaccess files and using bigger and better hosting, but I am unable to stop the attacks ...
11
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2answers
5k views

Best way to report a foreigner attacker's ip to authorities?

I have been under attack last week and I was able to trace down the attacker and get his IP address. The attacker was located in Germany but I live out of Europe? From your experience what is the ...
4
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2answers
520 views

If I send 4mbps of data to a friend with 4mbps connection, will I DoS 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 ...
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1answer
88 views

Dealing with a DDoS: horizontal vs vertical scaling?

I'm reading this paper about DDoS protection in AWS. One of the benefits of EC2 is that depending on the instance, it can scale for minimizing the effect of the attack. In the paper there are two ...
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0answers
113 views

How to keep my VPS server up on Hulk.py attack

This question in not duplicated, I tried everything that was published on stackexchange websites, but could not fix my problem. I have a web server. OS: Ubuntu 15.10 Configured on Apache2 Ram: 1.5 GB ...
11
votes
7answers
4k 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, ...
0
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0answers
21 views

Denial of service async Web service

Is it possible to perform a denial of service attack on an async service? Isnt the operating system supposed to release the thread? Im thinking it doesn't't matter as someone attacking a system would ...
0
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0answers
24 views

How does a firewall protect against denial of service attack? [duplicate]

I do not know much about firewalls etc, but I am curious as to how a firewall protects against Denial of service attacks. My understanding is that, sending a lot of requests(more than the server ...
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1answer
85 views

Sniffing or DOS attacks or MIM Attack [closed]

i'm preparing my bachelor's degree, i have to chose an attack, sniffing, dos, or MIM attack, I'm a bit lost, in my project i have to find a solution, how to detect one of this attacks, If you guys may ...
3
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1answer
49 views

Are there any risks to matching user-supplied regex against user-supplied inputs?

I have an IRC bot written in python3 that parses user requests for search and replace. Is there any risk of DoS or other attack by doing this?
4
votes
1answer
126 views

How to defend against a Spoofed-IP Blacklist DOS attack?

So I've implemented an IP Blacklist for the /login endpoint on my server. If any IP fails to login more than x number of attempts in x number of minutes the requesting IP is blacklisted for x number ...
3
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1answer
79 views

What other attacks can be deployed using IP spoofing other than DoS(and DDoS) attacks ?

I want to know the other attacks which are associated with IP spoofing because, we're trying to implement Source Address Validation (SAVA) and wanted to where else can Source Address validation ...