June 25, 2024

IPv4 Address Blacklisting: Causes and Solutions

If you’ve landed on this page, you probably have your IP address blacklisted for some sort of reason, or you’re just a curious fellow about the topic. Either way, you’ve come to the right place. IP blacklisting happens when network administrators prevent specific IP addresses from accessing certain networks due to suspicious malicious activity or a policy violation, and it’s not uncommon. This article breaks down the reasons why IP blacklisting happens and provides you with viable solutions to counter it. So, shall we?

What is an IPv4 Address?

Let’s go back to the basics before we delve deeper into our topic. For those who are exploring the world of networks, learning what an IPv4 address is is essential. To put it simply, an Internet Protocol (IP) address is your device’s unique identifier (think a digital name) that has four numbers separated by periods (e.g., 192.0.2.1). This allows you to connect and communicate with other devices online.

What is IPv4 Address Blacklisting, Really?

As we’ve mentioned earlier, IPv4 blacklisting involves blocking a certain IP address from accessing a network or service to prevent harmful activities. These activities include spamming, hacking attempts, or other malicious behaviors. Usually, the IPv4 address is added to a database maintained by various organizations, like email service providers (ESPs), spam filters, or cybersecurity companies.

Why Does IPv4 Address Blacklisting Happen?

There’s a long list of reasons why IPv4 address blacklisting happens, some of which are more serious than others. These include:

Emails– Yes, emails. You’re probably wondering what emails have to do with IPv4 address blocking. Well, if you send a huge chunk of unsolicited emails because of malware your computer is infected with, it can get your IP address blocked.
If you go around posting spammy or suspicious comments on online blogs and forums, your IPv4 address will most likely be blacklisted by content management systems and anti-spam services. Our advice? Be mindful of what you comment online.
Again with malware, but this time, website malware. If your website is hosting malware or phishing pages, your IP will undoubtedly be blacklisted.

Devices that are infected with malware and used as part of a botnet for malicious activities can lead to the associated IP addresses being blacklisted.
As unintentional as it may seem, repeated unsuccessful login attempts to various services can get your IP address blacklisted by intrusion detection systems (IDS) and firewalls. This is usually referred to as “brute-force attacks.”
IPv4 addresses involved in distributed denial of service (DDoS) attacks, meaning overwhelming a server with traffic to take it offline, can also be blacklisted by targeted networks and ISPS.

Your IP address is at risk of being blacklisted if you violate the terms of service of a network (rightfully so). It usually happens when you share illegal content or engage in fraudulent activities.
Sometimes getting your IPv4 address blocked can happen for a reason that’s none of your fault. These reasons include geographical restrictions. Certain services or content may not be accessible to you due to your geographical location. It’s also referred to as “geo-blocking.”

Last but not least, repeated attempts at hacking will get your IP address blocked. (Obvious, yeah?)

What are the Consequences of IP Blacklisting?

Being blacklisted is no fun, trust us. It has a domino effect on your online experience. This is how:

Any emails you send from a blacklisted IP address will be flagged as spam or rejected by recipient servers.
You won’t be able to access certain websites because security systems and content filters will block traffic originating from your blocked IP—also no fun.
Your online reputation will be profoundly and negatively affected because of your blacklisted IP. This will affect your brand’s credibility, and you don’t want that, do you?
You’ll miss out on a bunch of cool business opportunities because, you see, blacklisted IP addresses experience a decline in website traffic.

Yeah, the repercussions are serious.

How to Prevent and Resolve IPv4 Address Blacklisting?

So, how do you fix it if it happens to you? And how do you take measures so you don’t have to fix anything? Here are some of the things you can do:

If you’re having suspicions that your IP has been blacklisted, investigate it and try to find the potential cause.

Configure that firewall; it will prevent unauthorized access and brute-force attacks. Another way to prevent brute-force attacks is to implement rate-limiting on login attempts.
We figure it’s time you got yourself an intrusion detection system. IDS helps monitor and respond to suspicious activities on the network.
Not having anti-malware software installed on your device is not an option; it’s time to get one of those, too! It identifies any malicious software that might be causing the issue. (We recommend you do your scans regularly.)
Implement SPF, DKIM, and DMARC to authenticate emails and prevent them from being marked as spam.
Use reputation management services to check, clean, and maintain the reputation of your IP address. Recommended tools include Sender Score and Google Postmaster Tools.
If you’re sending a bulk of emails, make sure you have a double opt-in for email subscriptions in place to ensure recipients have agreed to receive them.
We can’t stress this enough, but your software needs to be up-to-date with the latest security patches.

Use throttling to limit the number of requests from a single IP address over a specific period of time.
Maintain a whitelist for trusted IPs that can bypass certain security checks and a greylist to temporarily block new IP addresses and monitor their behavior before granting access.
If you can’t access a certain service or network due to your geographic location, use a VPN to avoid getting your IP blacklisted.
Be careful with those email attachments! Some email attachments or links can compromise your system.
We hate to break it to you, but public Wi-Fi networks can be your IP address’s demise because they’re usually unsecured. So, avoid them.
If your IP has been blacklisted, contact the relevant organization and submit a delisting request. You’ll need to provide evidence that the issue has been resolved, though.
A drastic measure would be changing your IP address, if applicable. If blacklisting persists and you have a static IP address, consider contacting your ISP to request a new IP.

And there you have it! As we said earlier (and probably you found out yourself), IP blacklisting is no fun. It is a serious issue that can significantly disrupt your online experience. Remember, a scan a day keeps IP blacklisting away! Implement strong security practices and be cautious online to avoid the pitfalls of IP blacklisting.

If you’re considering getting an IPv4 address, reach out to IPv4Mall, your trusted IP address broker!