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 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 ...
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3answers
968 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 ...
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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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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 ...
5
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0answers
107 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 ...
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1answer
48 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 ...
22
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3answers
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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 ...
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1answer
87 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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1answer
129 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?
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1answer
276 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 ...
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Explanation for these entries in the Suricata fast.log?

We have installed Suricata on our system. We have the following similar lines in our fast.log. Can anyone explain these lines? 03/17/2016-17:18:52.744707 [**] [1:2200075:1] SURICATA UDPv4 invalid ...
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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 ...
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39 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 ...
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2answers
68 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 ...
2
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2answers
53 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
858 views

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 ...
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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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1answer
47 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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1answer
94 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 ...
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1answer
64 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 ...
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2answers
4k 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
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2answers
122 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 ...
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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
55 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
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0answers
56 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 ...
2
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1answer
61 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 ...
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1answer
58 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 ...
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3k 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?
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3answers
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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 ...
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2answers
4k 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
486 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
80 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
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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 ...
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7answers
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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, ...
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0answers
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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 ...
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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
75 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 ...
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1answer
44 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?
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1answer
113 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 ...
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1answer
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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 ...
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1answer
163 views

How to test DOS attacks through Router?

One of my clients has been told by their ISP that a DoS attack has happened and they have provided the logs of Juniper router. What is the criteria in routers on which we can confirm DoS attack is ...
2
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1answer
174 views

Initial handshakes of attacks via client-initiated renegotiation

As far as I understand after reading this beautifully explained answer, MiTM data injection attacks via client-initiated renegotiation can only happens if the attacker is already in a connection with ...
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2answers
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Can an ISP or webpage block me from accessing it if I'm sending too many requests? [closed]

I visit webpage where there is a comment section. These comments have a number of likes/dislikes as 2 numbers. If I vote, a cookie is created and I can't vote again (but I can if I delete my cookies, ...
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2answers
63 views

Should I really treat memory leaks like classical bandwith dos?

I recently found that a big company use an outdated product in their file-storage servers (I got the hidden name and version). The bug is corrected in recent version, but they weren’t any cve or ...
0
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1answer
819 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 ...
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2answers
70 views

How can perpertrators of denial of service attacks, determine the impact their attack has had?

Although I know how a user could mitigate Dos attacks and detect their presence e.g. checking packets received and sent, comparing current CPU usage to normal, comparing network usage to normal etc. ...
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1answer
99 views

How effective are firewall rate limiting rules for slowing down brute force and DOS attacks?

I am investigating methods to slow down the rate at which attackers can make brute force attempts against my webserver's SSH and HTTP services. I have come across many articles as well as the ...
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2answers
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DoS Reflection attack using CharGen protocol

I'm researching DoS Reflection attacks w/ amplification, and Wikipedia says that one of the "worst" amplification services is the Character Generator Protocol. Frankly, I have never heard of this ...
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Is there any protection against malicious devices on a CAN bus?

CAN (controller area network) is a bus used in all modern cars. You can read a lot of the cars information over this bus and I think (but I'm not too sure about this) that some critical control ...