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221

This seems to be a persistent question. IP addresses aren't secrets. Every website you go to must know your IP address. There's no reason to not give away your IP address. Many companies have firewalls that only allow certain addresses through to certain ports. This is a relatively common way of controlling access to resources with minimal effort. ...


198

Let's say that you run a shop. Every day, you might get a few hundred customers. One day, you get tens of thousands of people coming in, who get in the check-out line, buys a trinket, and then gets right back in line to repeat. Obviously, you are losing business from authentic customers who must wait hours in line. Now, you hire a security guard at the ...


164

The concept is "reducing the threat surface". If there is an expectation that no connections will be made from a certain geographic area, then it makes sense to block that area, because, by definition, it is not legitimate. In theory. (For a health provider, it's a weird choice since customers might want to manage their health while traveling, but this is a ...


160

Network engineer with Border Gateway Protocol (BGP) experience here. Yes. But usually the attack would have to be for a larger address block and (as Eevee commented) require an attacker with specific skills and access. If someone calls you and claims that your IP is hacked, they are probably a scammer. Hang up! Back to the question: Let’s assume the “...


116

TL; DR The multiple source IPs are what makes them so hard to defend against. For the longer answer we look at the name. DDoS attack. That first D stands for distributed. In other words, there is no one IP to block. Or two, or three, or even four.. There are hundreds or thousands of unique IPs. Usually DDoS attacks originate from a hacker in control of a ...


112

The most likely source of this information is your browser's WebRTC implementation. You can see this in the source code of ip-api.com. From https://github.com/diafygi/webrtc-ips, which also provides a demo of this technique: Firefox and Chrome have implemented WebRTC that allow requests to STUN servers be made that will return the local and public IP ...


100

The IPv4 address range isn't that big. A class A network (/8) has about 16 million hosts, and in theory there is 256 of them. As a result, the internet has about 4,294,966,784 hosts. Of course, this is an approximation. Many address ranges are actually reserved (e.g. 127.0.0.0/8, 10.0.0.0/8), and others are actually one address that represent a NAT-ed ...


98

If you are on the same network you can open up a Terminal: ping your_ip_address hit Ctrl-C on the keyboard to stop pinging then do a: arp -a a list should appear, look for the ip you just pinged and next to it is the MAC address of the device.


88

IP address bans have flaws as you mention, but I think the primary reason they are used is simply that there aren't really any better alternatives. Other identifying features, like browser user agent, cookies, browser fingerprint, etc. are even easier to spoof or circumvent. There are plenty of extensions you can use to change your user agent or fingerprint, ...


88

No, they would have to have access to your browser cookies in order to abuse them to log into a site you left logged in. Merely knowing your public IP address would not allow them to log into any website. If you are asking this question though, I would not be so sure that there are "immense barriers" between them and your personal computer. A good hacker can ...


84

You can change your IP to whatever you want; that's trivial. But that will not work the way you want to. Let's say the store's ISP is Apple Networks, and their IP range is 1.2.3.0 to 1.2.3.255. You note that and get home. Your home network is from Avocado Networks, and their IP range is 2.3.4.5. You change your IP to 1.2.3.123 and wait. Nothing happens. You ...


73

First: almost every single site out there is an "IP logger". Every server logs at least this information: IP address of the client Browser type and version Operating system Which site they came from (the Referer) So, not only does this site have your IP address, but each site you ever visited has your IP address in their own logs. A few, very few sites won'...


72

Since you asked specifically what the website will see, rather than any intermediary watching your network connection, we should think in terms of requests: Your old ("native") IP will disconnect any long-running requests, and stop making any new requests. Your new (VPN) IP will connect and start making requests. On their own, those two events will be ...


71

There is some widespread confusion about NAT. NAT has never been meant to be used as a security feature. However, it so happens that in most cases (not all), when a machine has access to the Internet through NAT only, then the machine is somehow "protected". It is as if the NAT system was also, inherently, a firewall. Let's see how it works: An IP packet ...


71

Botnet If someone has access to a botnet, even a small one, they could change the IP that their actions are coming from several times per minute or flood their actions from a million IPs in any given moment. Non-botnet For individuals without a botnet, there are several methods, including resetting their ISP modem, which, in some cases, resets the IP. ...


69

I suspect that your Wordfence plug-in is blindly trusting the X-Forwarded-For header. This header is used by proxies to indicate the IP address of the computers sending traffic trough them, but can easily be spoofed. It is also very well possible that some of the visits from “0.0.0.0” aren't malicious, but simply users behind a misconfigured ...


69

This is not a sign of a problem for your server. There's an important detail here, which is: 104.27.182.86 is not your server. That IP belongs to cloudflare. Cloudflare provides a large number of services to websites and sits in between the public internet and a server. Someone who uses Cloudflare doesn't point their DNS to their own server - they point ...


67

The answer to this question very much depends on the security posture of your site, which decides whether the risk of unauthorised access is greater or lower than the risk of Denial of Service for some users. For high risk sites, I might go with the blocking option, especially where most of the user base is likely to be home users and therefore is likely to ...


62

Why would a company I am about to do some work (working from home) for, ask for my IP address? What would they need it for? Should I be worried? Thanks More than likely, they need to be able to white list your IP address, or IP range, to allow remote connections from your home. They need to know who's on their network, and why. There's nothing to worry ...


61

The problem with this scenario is that emails are typically not sent from the device itself, but from a central service. In order to do what you want, the investigators would have to make a few hops: to the email service (gets the user account details, including the IP the user used to connect with) to the ISP the device used at the time of sending (gets ...


59

Your IP is a public address and has nothing to do with your Facebook account. Just knowing it does not help someone to 'hack' you. In the same way, knowing your IP does not increase your threat of your computer being hacked. He's blustering.


59

Connecting 'things' to the Internet is becoming common because of the benefits of remote communication. You can have your camera upload its footage to a cloud storage server, or be able to view the camera remotely, for instance. Any device on the Internet is exposed and subject to network mapping. The entire Internet is constantly being scanned, and once an ...


58

TL;DR Tor provides anonymous web browsing but does not provide security. VPN Services provides security (sort of) and anonymity, but the anonymity might be more in question depending on the service. Since you're depending on them not logging pieces of information that may or may not be able to be traced back to you. VPNs Traditional A traditional ...


54

You don't have to worry about spoofing the IP from a different connection, because returned TCP packets would not make it to the attacker in that scenario. So all you have to worry about is how easy it is for the attacker to make use of that IP: Is that IP shared between multiple computers in the office? Can that IP be used on WiFi? How well is the ...


53

An IP address is nothing private. Nowadays it's possible to scan the entire IPv4 Internet within minutes. ZMAP, for example, is a tool that can be used for such scans. NMAP can be used on IP addresses to scan for open ports or services, like SSH. There are also Online Databases like Shodan with huge lists of devices and services on the internet.


51

Static or dynamic IP is a non-issue. But since you brought up cameras, you should know that many IP cameras have VERY poor security. Many of these cameras have a known bad firmware in them that allows unauthenticated download of the entire memory of the device via simply going to /proc/kcore, without the need to authenticate. This allows anyone to obtain ...


49

IP Spoofing is NOT IP Hijacking which is causing confusion for anyone reading this. IP Spoofing at its minimum / bare bones explanation is also called impersonation. Let's have an ASCII look at what it does, and how it happens: You (1.2.3.4) --> connect to your bank --> Bank (2.2.2.2) In spoofing, I can pretend to be anyone I want, if I am on your ...


47

A common method to get the internal IP address is by using RTCPeerConnection in JavaScript. http://ip-api.com/ for example, is calling a javascript function named "gi" that contains the following code: ... o = window.RTCPeerConnection || window.mozRTCPeerConnection || window.webkitRTCPeerConnection, ... Technically, this is done by setting a callback on ...


47

However, in this scheme, couldn't an impostor just present the certificate after getting it from the real server? An impostor cannot present, and take advantage of, the real server's certificate unless it also has the matching private key. This is true whether the SAN DNS entry or IP entry are used to identify the certificate being presented.


46

Revealing your IP address doesn't compromise the security of your machine. If an attack on your machine is untargetted (i.e. the attacker just wants to use it to send spam or fishing emails, or as a proxy for targetted attacks), your machine will be scanned at random, not based on the IP address that may be posted in a forum. If the attack is targetted, the ...


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