How to solve when the DoS attack ACK scan in a simple way?
When a DoS attack, ACK scan might be frightening at first since you don’t understand what it is, and you instantly fear that your personal information has been exposed. The first step to solving the problem is figuring out how to diagnose the issue. In this guide, we will cover three easy steps that will help you when a DoS attack ACK scan attacks your site. When this attack happens on your site, with the log file on, it will be easier to find out what happened.
Why? The first is because you need to know exactly which page was hit by the attack ACK scan because if you don’t understand who is doing the scanning then there’s no point in having it. The second reason is that you need to know why it happened if it’s not just to take down your website while making sure your website has a DoS in place. Lastly, if something goes wrong after that step and you have no idea what happened, then at least you will have a clue as to what actually went wrong.
What is ACK scanning?
Well, there are two methods of detecting open ports on a target server. The first method is simply sending an ICMP echo request message and listening for ICMP echo reply messages through the use of ping. This can be very effective in finding out whether a host is up or down, but it proves ineffective when trying to find open ports because the message packets will not pass through closed ports; it will only pass through open ones.
How does ACK scanning works?
ACK scanning is another method of port scanning that uses the ACK flag. This works in a similar way to ping, except it will only send packets to closed ports and notice if they are closed by receiving an ICMP Port Unreachable message. If the port is open, the host will send back an RST packet, acknowledging that there was a problem with receipt of the packet. ACK scanning and SYN scanning both require root privileges on UNIX based systems. To perform this type of scan manually, you have to use netcat or other utilities like nmap.
Why is ACK scanning considered a better method?
It’s efficient and easy to use. When performing an ACK scan, you open the port 20, but in a way that the port will not be closed by ICMP. This makes it difficult for the target host to close the port after you have opened it to verify its state. This works especially well for services that have many ports. If you are able to open all of these ports in parallel, then you will get more information about your target than if you only run a single port scan.
At the point when a DoS assault, ACK sweep may scare from the start since you fail to really see what it is, and you immediately dread that your own data has been uncovered. The initial step to tackling the issue is sorting out some way to analyze the issue. In this aide, we will cover three simple tasks that will help you when a DoS assault ACK filter goes after your site.
Solve when the DoS attack ACK scan:
- Protect Your Network:
With a laptop and a router, you will set up your home network. You can also set up a mobile hotspot on your phone if you have wifi.
- Change the Router DNS:
With the WAN IP of the router, go to Google DNS and change it to 8.8.8.8 or 8.8.4.4 while setting it up as static or DHCP in your router configuration page (CCNA students are advised to do this step only)
- Detecting DoS Attack:
On your browser, click the network status and attach it to the protocol TCP. Then, when an attack is detected, refer to the log file generated by your browser.
- Fix the Issue:
It is important to note that this guide is not a definitive all-in-one solution for all possible DoS attacks, but it is a good start if you are new to the field. This guide is written as though you have a test environment such as a virtual machine or even just localhost:80 on your host machine; this is because without access to the real server, you will be unable to access the log files, and therefore diagnose the problem correctly. If you are not an expert, it is best to contact a professional IT helpdesk or Internet service provider.
How to discover malicious ACK scans?
- Detect:
With the use of PassiveTotal, you can easily detect malicious ACK scans.
- Prevent:
You can reduce the severity and damage of such attacks is to use a blacklist solution like ModSecurity or Suricata.
- Block:
You can block the suspicious IP addresses and port numbers.
- Solution:
If it causes DoS, you have to block it by root DNS record or firewall rule. Security protocols used by different online services, including those offered by ISPs, can be classified by the following two categories: those that impose restrictions on institutions and legal entities, and those that impose restrictions on individuals.
How to prevent these DoS attacks?
- Preventing DoS attacks:
You can prevent these DoS attacks by installing a firewall. You should also ensure that you have network level security protocols and services.
- Blocking DoS attacks:
When a DoS attack is identify, you should block the suspects using root DNS records, filter rules in your firewall. Or by using a separate network appliance with an IPS function (such as an IDS/IPS). In this case, it is important that you have a routing rule with no-cache to your edge router for its IP address.
- Blocking illegal access:
Addition to using your firewall, you can block illegal access to your IP address by using a firewall rule.
- How should you protect yourself?
In general, you can use the following methods to protect yourself: Use a VPN or proxy to hide your IP address. Use a Smart DNS service to change your location. Recent studies have shown that thousands of DoS attacks occur on the internet every day. And in many cases they go unanswered by offending ISPs, sites or network operators. From the end user perspective this is unfortunate. Since if you are targeted by a DoS attack and do not have a plan in place. You will be in for one long unpleasant ride until the attack stops, or until your bandwidth runs out. (most of which don’t let you know when it’s running out).
Final Verdict:
Well, we hope that this article will be very useful for you in understanding the DoS attacks and how to solve them. If you have any query regarding this article, then please share with us. We are not responsible or liable for any injury, damage, or loss of any kind which any person makes when using our content. Please use the knowledge responsibly. The subsequent explanation is that you really want to know why it worked out. In the event that it’s not simply to bring down your site. It ensures the site has a DoS set up. Ultimately, assuming something turns out badly after that step and you have no clue about what occurred. Then basically you will have an idea regarding what really turned out badly.