Rusty  Shanahan

Rusty Shanahan

1597077480

What is DDoS attack ?

Distributed Denial of Service (DDoS) attacks are becoming more

frequent and the size of these attacks is increasing rapidly on every

year. This increases the load on the networks of Internet Service

Providers (ISPs) and many Cloud computing providers. Cloud

computing is an emerging technology and adopted by many Cloud

providers. But, there are many issues and one of them is Distributed

Denial of Service(DDOS). Distributed Denial of Service (DDoS) attack

is the most prominent attacks in this area of computing. DDoS is the

single largest threat to internet and internet of things. The frequency

and sophistication of Distributed Denial of Service attacks (DDoS)

on the Internet are rapidly increasing. In this article, we conduct an

up-to-date review of essential Cloud Network threats and present

a methodology for evaluation of existing security proposals. Based

on this, we introduce a comprehensive and up-to-date survey of

proposals intended to make the Network Infrastructure highly

secure and introducing new methods for detection and mitigation

of routing instabilities and these generic countermeasure model

can be used to prevent secondary victims and to prevent DDoS

attacks. These taxonomies define varies similarities and different

patterns in Dos and DDoS attacks, configuration, functional tools, to

assist in further improvement on Network Infrastructure security and

proposed a solution to countering DDoS attacks.

D- DoS attacks can be classified further as the primary target is

to congest the network with a massive amount of the bandwidth

Utilization and it could cause the network abruption to the victim

network.

Image for post

Attack Classifications: (Figure 1) Besides, these classifications, all

forms of attacks fall under these two functions.

Connection-based attack: This type of attacks can be carried out

through an established connection of any client and server by using

certain connection-oriented protocols.

Connection-less attack: An attack that doesn’t require a standard

protocol-based session. Connection-less meant to be formally

established before a server can send the “data packets” — typically a

basic unit of communication information which is transferred over a

digital network to a client.

**Volumetric Attack: **The Specific goal of this type of attack is to

cause the congestion traffic while sending the data packets over the

line and it would cause a bandwidth to overwhelm the scenario. Especially,

most of the attacks are executed using botnets. botnet is a group of

agent handlers in a DDoS attack which provides the attacker with the

ability to wage a much larger and more wild attack than a DoS attack

while remaining anonymous on the Internet. It is measured by the

number of received bits per second (bps).

Protocol Attack: In general, this type of attack focal point is

on actual web/DNS/FTP servers, core Routers and switch, firewall

devices and LB (load balancers) to disrupt the well-established

connections, and also causing the exhaustion of their limited number

of concurrent sessions on the device. It is measured by the number of

received packets per second (PPS).

Application Layer Attack: It is also known as Connection-oriented

attacks. Application attacks occur in the Layer 7 of an OSI Model.

Most of the Applications are under vulnerable scenarios by consisting

of many loopholes. This specific type of attack is pretty much hard to

detect because these sophisticated threats are generated from the

limited number of attack machines, on top of that it’s only generating

low traffic rate which appears to be legitimate for the victim to realize.

It is measured by the number of received requests per second (RPS).

#technology #security #cloud-computing #computer-sciecne #ddos-attack #cloud

What is GEEK

Buddha Community

What is DDoS attack ?
Angela  Dickens

Angela Dickens

1598322120

DDoS attacks have evolved, and so should your DDoS protection

The proliferation of DDoS attacks of varying size, duration, and persistence has made DDoS protection a foundational part of every business and organization’s online presence. However, there are key considerations including network capacity, management capabilities, global distribution, alerting, reporting and support that security and risk management technical professionals need to evaluate when selecting a DDoS protection solution.

Gartner’s view of the DDoS solutions; How did Cloudflare fare?

Gartner recently published the report Solution Comparison for DDoS Cloud Scrubbing Centers (ID G00467346), authored by Thomas Lintemuth, Patrick Hevesi and Sushil Aryal. This report enables customers to view a side-by-side solution comparison of different DDoS cloud scrubbing centers measured against common assessment criteria. If you have a Gartner subscription, you can view the report here. Cloudflare has received the greatest number of ‘High’ ratings as compared to the 6 other DDoS vendors across 23 assessment criteria in the report.

The vast landscape of DDoS attacks

From our perspective, the nature of DDoS attacks has transformed, as the economics and ease of launching a DDoS attack has changed dramatically. With a rise in cost-effective capabilities of launching a DDoS attack, we have observed a rise in the number of under 10 Gbps DDoS network-level attacks, as shown in the figure below. Even though 10 Gbps from an attack size perspective does not seem that large, it is large enough to significantly affect a majority of the websites existing today.

#ddos #attacks #gartner #trends #network #neural networks

Justyn  Ortiz

Justyn Ortiz

1597402800

Mitigating a 754 Million PPS DDoS Attack Automatically

On June 21, Cloudflare automatically mitigated a highly volumetric DDoS attack that peaked at 754 million packets per second. The attack was part of an organized four day campaign starting on June 18 and ending on June 21: attack traffic was sent from over 316,000 IP addresses towards a single Cloudflare IP address that was mostly used for websites on our Free plan. No downtime or service degradation was reported during the attack, and no charges accrued to customers due to our unmetered mitigation guarantee.

The attack was detected and handled automatically by Gatebot, our global DDoS detection and mitigation system without any manual intervention by our teams. Notably, because our automated systems were able to mitigate the attack without issue, no alerts or pages were sent to our on-call teams and no humans were involved at all.

Attack Snapshot - Peaking at 754 Mpps. The two different colors in the graph represent two separate systems dropping packets.

During those four days, the attack utilized a combination of three attack vectors over the TCP protocol: SYN floodsACK floods and SYN-ACK floods. The attack campaign sustained for multiple hours at rates exceeding 400-600 million packets per second and peaked multiple times above 700 million packets per second, with a top peak of 754 million packets per second. Despite the high and sustained packet rates, our edge continued serving our customers during the attack without impacting performance at all

The Three Types of DDoS: Bits, Packets & Requests

Attacks with high bits per second rates aim to saturate the Internet link by sending more bandwidth per second than the link can handle. Mitigating a bit-intensive flood is similar to a dam blocking gushing water in a canal with limited capacity, allowing just a portion through.

Bit Intensive DDoS Attacks as a Gushing River Blocked By Gatebot

In such cases, the Internet service provider may block or throttle the traffic above the allowance resulting in denial of service for legitimate users that are trying to connect to the website but are blocked by the service provider. In other cases, the link is simply saturated and everything behind that connection is offline.

Swarm of Mosquitoes as a Packet Intensive DDoS Attack

However in this DDoS campaign, the attack peaked at a mere 250 Gbps (I say, mere, but ¼ Tbps is enough to knock pretty much anything offline if it isn’t behind some DDoS mitigation service) so it does not seem as the attacker intended to saturate our Internet links, perhaps because they know that our global capacity exceeds 37 Tbps. Instead, it appears the attacker attempted (and failed) to overwhelm our routers and data center appliances with high packet rates reaching 754 million packets per second. As opposed to water rushing towards a dam, flood of packets can be thought of as a swarm of millions of mosquitoes that you need to zap one by one.

Zapping Mosquitoes with Gatebot

Depending on the ‘weakest link’ in a data center, a packet intensive DDoS attack may impact the routers, switches, web servers, firewalls, DDoS mitigation devices or any other appliance that is used in-line. Typically, a high packet rate may cause the memory buffer to overflow and thus voiding the router’s ability to process additional packets. This is because there’s a small fixed CPU cost of handing each packet and so if you can send a lot of small packets you can block an Internet connection not by filling it but by causing the hardware that handles the connection to be overwhelmed with processing.

Another form of DDoS attack is one with a high HTTP request per second rate. An HTTP request intensive DDoS attack aims to overwhelm a web server’s resources with more HTTP requests per second than the server can handle. The goal of a DDoS attack with a high request per second rate is to max out the CPU and memory utilization of the server in order to crash it or prevent it from being able to respond to legitimate requests. Request intensive DDoS attacks allow the attacker to generate much less bandwidth, as opposed to bit intensive attacks, and still cause a denial of service.

Automated DDoS Detection & Mitigation

So how did we handle 754 million packets per second? First, Cloudflare’s network utilizes BGP Anycast to spread attack traffic globally across our fleet of data centers. Second, we built our own DDoS protection systems, Gatebot and dosd, which drop packets inside the Linux kernel for maximum efficiency in order to handle massive floods of packets. And third, we built our own L4 load-balancer, Unimog, which uses our appliances’ health and other various metrics to load-balance traffic intelligently within a data center.

In 2017, we published a blog introducing Gatebot, one of our two DDoS protection systems. The blog was titled Meet Gatebot - a bot that allows us to sleep, and that’s exactly what happened during this attack. The attack surface was spread out globally by our Anycast, then Gatebot detected and mitigated the attack automatically without human intervention. And traffic inside each datacenter was load-balanced intelligently to avoid overwhelming any one machine. And as promised in the blog title, the attack peak did in fact occur while our London team was asleep.

So how does Gatebot work? Gatebot asynchronously samples traffic from every one of our data centers in over 200 locations around the world. It also monitors our customers’ origin server health. It then analyzes the samples to identify patterns and traffic anomalies that can indicate attacks. Once an attack is detected, Gatebot sends mitigation instructions to the edge data centers.

#ddos #security #gatebot #attacks #syn #ack #network layer

DDoS Attacks Skyrocket as Pandemic Bites

The first half of 2020 saw a significant uptick in the number of distributed denial-of-service (DDoS) attacks compared to the same period last year — a phenomenon that appears to be directly correlated to the global coronavirus pandemic.

Neustar’s Security Operations Center (SOC) saw a 151 percent increase in DDoS activity in the period, including one of the largest and longest attacks that Neustar has ever mitigated – that attack came in at 1.17 terabits-per-second (Tbps), and lasted five days and 18 hours.

“These figures are representative of the growing number, volume and intensity of network-type cyberattacks as organizations shifted to remote operations and workers’ reliance on the internet increased,” the company noted in its first-half status report, released on Wednesday.

#web security #coronavirus #covid-19 #cyberattacks #ddos #denial of service #healthcare #internet usage #neustar #pandemic #trend report #volumetric attacks #work from home

Rusty  Shanahan

Rusty Shanahan

1597077480

What is DDoS attack ?

Distributed Denial of Service (DDoS) attacks are becoming more

frequent and the size of these attacks is increasing rapidly on every

year. This increases the load on the networks of Internet Service

Providers (ISPs) and many Cloud computing providers. Cloud

computing is an emerging technology and adopted by many Cloud

providers. But, there are many issues and one of them is Distributed

Denial of Service(DDOS). Distributed Denial of Service (DDoS) attack

is the most prominent attacks in this area of computing. DDoS is the

single largest threat to internet and internet of things. The frequency

and sophistication of Distributed Denial of Service attacks (DDoS)

on the Internet are rapidly increasing. In this article, we conduct an

up-to-date review of essential Cloud Network threats and present

a methodology for evaluation of existing security proposals. Based

on this, we introduce a comprehensive and up-to-date survey of

proposals intended to make the Network Infrastructure highly

secure and introducing new methods for detection and mitigation

of routing instabilities and these generic countermeasure model

can be used to prevent secondary victims and to prevent DDoS

attacks. These taxonomies define varies similarities and different

patterns in Dos and DDoS attacks, configuration, functional tools, to

assist in further improvement on Network Infrastructure security and

proposed a solution to countering DDoS attacks.

D- DoS attacks can be classified further as the primary target is

to congest the network with a massive amount of the bandwidth

Utilization and it could cause the network abruption to the victim

network.

Image for post

Attack Classifications: (Figure 1) Besides, these classifications, all

forms of attacks fall under these two functions.

Connection-based attack: This type of attacks can be carried out

through an established connection of any client and server by using

certain connection-oriented protocols.

Connection-less attack: An attack that doesn’t require a standard

protocol-based session. Connection-less meant to be formally

established before a server can send the “data packets” — typically a

basic unit of communication information which is transferred over a

digital network to a client.

**Volumetric Attack: **The Specific goal of this type of attack is to

cause the congestion traffic while sending the data packets over the

line and it would cause a bandwidth to overwhelm the scenario. Especially,

most of the attacks are executed using botnets. botnet is a group of

agent handlers in a DDoS attack which provides the attacker with the

ability to wage a much larger and more wild attack than a DoS attack

while remaining anonymous on the Internet. It is measured by the

number of received bits per second (bps).

Protocol Attack: In general, this type of attack focal point is

on actual web/DNS/FTP servers, core Routers and switch, firewall

devices and LB (load balancers) to disrupt the well-established

connections, and also causing the exhaustion of their limited number

of concurrent sessions on the device. It is measured by the number of

received packets per second (PPS).

Application Layer Attack: It is also known as Connection-oriented

attacks. Application attacks occur in the Layer 7 of an OSI Model.

Most of the Applications are under vulnerable scenarios by consisting

of many loopholes. This specific type of attack is pretty much hard to

detect because these sophisticated threats are generated from the

limited number of attack machines, on top of that it’s only generating

low traffic rate which appears to be legitimate for the victim to realize.

It is measured by the number of received requests per second (RPS).

#technology #security #cloud-computing #computer-sciecne #ddos-attack #cloud

What is DDoS Attacks and How is it done?

In this flood, I will talk about DDoS (Distributed Denial of Serviceattacks on web applications and some of the methods of doing these attacks.

The type of traffic we want to accept from the outside world (eg 443 HTTPS) and therefore allowed to pass through the Firewall can be created by malicious people in a high volume that our servers cannot meet, and our service may be interrupted.

As an example, let’s assume that a web application is served from a data center with an upload speed of 750 Mbps. If maliciously organized bots generate 750 Mb of traffic per second to the application, they prevent the application from serving. This attack is called **DoS **(Denial of Service) since users are prevented from receiving service. If 750 Mbps is created from only one data center or one country, the attack is easily eliminated by filtering the traffic from the firewalls of the data center provider from the relevant IP or IP blocks.

In order to increase the effectiveness of the attack and to ensure its continuity, such attacks are usually made from many countries and countless IPs, it is not possible to separate the related IPs from normal traffic. This type of DoS attack is called DDoS, in other words, Distributed DoS.

The most effective DDoS attacks are done by Botnets that infect mobile phonescomputers, or IoT devices and control these devices with the malware they place on them. The device that is infected with malware and used in an attack is called Zombie.

Malicious people can remotely control Botnets consisting of devices they zombie, and make DDoS attacks whenever they want, and even this mechanism is offered by these people as a service for a fee.

In 2015, in the 5-day DDoS attack on GitHub, a country injected an extra JavaScript code into a certain percentage of web page requests from the world to the pages served in their country, causing the user’s browser to call several pages from Github.

#cybersecurity #devsecops #devops #ddos-attack #botnet