The first thing we are going to do is get to know the concept of “public IP” and the two different classes that exist. We will also address the issue of information that can be extracted through knowing a public IP. Then we will explain what happens when my public IP address is leaked and also how we can protect ourselves.
The concept of IP address in our home networks and its classes
An IP address we can say is a logical and unique identifier for each of the computers connected to a network. Regarding the classes of IPs, we could say that there are basically two: the private IP and the public IP.
Refering to Private IP, is the one that will identify at the local level each of the computers that are connected to our home network. In this case, we refer to each of the IP addresses that the router assigns to the PC, the smartphone and other devices. If we wanted we could establish one manually on the router or in Windows TCP / IP.
According to the Public IP we can define it as the identifier of our network facing the Internet. An important difference with respect to the private one is that we cannot put the one we want. Thus, our Internet service provider or ISP will be in charge of assigning one. On the other hand, within the public IP we have two classes:
- The Fixed or static public IP, is when we will always have the same and it will not change.
- A Dynamic public IPOn the contrary, it is the one that can be exchanged for another. The change will occur when our router is turned off or after a period of time established by the ISP.
Today, the vast majority of customers have a dynamic public IP for their home network. The great advantage it has is the increase in security since although today we could be reachable, tomorrow we may have changed IP. In that sense, if my public IP address were leaked, I would run less risk, because the IP is being renewed, and therefore we would be more secure.
On the other hand, we have the static IP which is the one that organizations usually hire to set up their servers in exchange for an extra payment on the Internet bill. In this case, if my public IP address was leaked, the situation would be more worrying since the cybercriminal could carry out his misdeeds day after day.
What they can get to know when my public IP address is leaked
The moment we obtain a public IP, it can provide us with very relevant information. If you do it using yours, you will be able to see the trail that you will later leave on the Internet. If we use our Internet browser on Windows, Android or Linux we can easily find out. To discover our public IP we are going to do it using the web which-es-mi-ip.net and by clicking on the previous link we can discover the public IP address that we have assigned. This is the result I have obtained using a Windows 10 PC:
A priori, it may not seem like a lot of information, but as we will see below, it is quite a lot:
- The public IP we have.
- The internet provider, in this case Telefónica de España.
- Public IP class that when pointing to static ip indicates that it is static or fixed. In case of being dynamic it does not put anything.
- Country Spain.
- Proxy: no, this means that we enter the Internet directly and that we do not browse through a proxy.
But that’s not all, if we click on the button with the red box Geolocate IP that you have above is going to offer you more detailed information.
In most cases this geolocation is very exact and it will show us the city where that public IP is located. On the other hand, if we wanted to check a public IP, after writing it down, on the same website we could check it from here .
Its way of using it is very simple, in the IP address we put the one we want to find out, and then we click on the magnifying glass icon. In this case we see that it is from Denmark.
However, we could also find out more. If we do a port scan we can know if it has an FTP or web server, and also if it has any open ports. To perform this task we can perform a port test through a web. Here we have to type the public IP, and then add the port or ports that we want to check. Here we can check port ranges using this format (1-80), separating them by commas to make them one by one (20,21) or in applications put the name to add the ports.
Therefore, if my public IP address is leaked, as you have seen, they will be able to obtain a lot of information from us. In addition, we must not forget online tools such as Shodan That allows us to put an IP address and check if it has different services running, and we can even know if any of these services is vulnerable to a security failure to later exploit this failure and be able to gain full control of the equipment.
Then we also have the Adware Tracking Cookies which are a type of tracking cookie that is used to obtain information about the browsing habits of users. These and other types of cookies can end up being an aid to stop filtering my public IP address. In that sense, clearing the cache and cookies weekly to improve privacy may be a good idea.
How it affects my IP address being leaked and how it can be prevented
Throughout this tutorial we have seen the consequences if my public IP address is leaked.
Without a doubt, one of the most important risks that we are going to have is that will negatively affect our privacy. We have already seen all the information they could get from us, such as location. We must also bear in mind that both the DNS servers and our internet provider will have a lot of information about our browsing history. In the hypothetical event that your public IP address, browsing history, account information and location were discovered, a cybercriminal could discover your personal identity.
Therefore, it also goes negatively impact our safety. A solution that we could adopt to improve that security would be the use of a VPN or a proxy to improve our anonymity. However, from RedesZone we do not recommend using the free types because in the end the product is oneself and they usually end up selling certain information. That is why it is better to use a paid one like Surfshark, NordVPN, HMA VPN or PureVPN.
In summary, by leaking my public IP address we are going to have privacy and security problems.