What an IP reputation attack is and how to protect your network

What is IP reputation?

Most email service providers and internet service providers have their own IP reputation monitoring practices. Many cybersecurity tools also maintain their own IP reputation databases. Because of this, your IP reputation can vary. 

What is the importance of IP reputation?

Since the early 2000s, IP reputation has played a key role in filtering spam, detecting threats, and protecting users from malicious activity. Simply put, if the emails you send have high bounce rates, frequently get marked as spam, or are linked to malware, your IP reputation can suffer. This situation may lead to email providers filtering your messages into spam folders or security tools flagging your site. Maintaining a strong IP reputation — alongside proper email authentication — helps ensure reliable email delivery, website accessibility, and overall online credibility.

What is an IP reputation attack?

An IP reputation attack, also known as IP hijacking, spam abuse, or server compromise, occurs when a hacker infiltrates a website or server and uses its IP address for malicious purposes. For example, they might exploit an email server to bombard contacts with spam, damaging the IP's reputation.

When legitimate companies are targeted by IP reputation attacks, maintaining a secure online presence becomes challenging. Even if your IP reputation was previously positive, malicious activity can still damage it, often without your knowledge. 

How does an IP reputation attack work?

Hackers use various strategies to find and compromise their targets’ IP addresses. Many social media platforms and online forums store user IP addresses, and if these platforms are compromised, hackers may potentially access this data. 

On top of that, cybercriminals may use social engineering tactics to exploit an IP address. To do so, they send emails, post ads, or create websites that look legitimate. Behind the scenes, these digital assets are collecting your IP address as you interact with them. 

Once these threat actors have access to your IP address, they can use this information to hack into your networks and devices. From there, they can use your IP address for various malicious purposes. Examples include: 

• Using your email servers to send large volumes of spam or phishing emails.
• Redirecting website visitors through malicious proxies or injecting harmful scripts.
• Hacking into devices associated with your IP address to build botnets and launch a DDoS attack.
• Creating an open proxy with your IP address to mask other types of cyberattacks.

If this malicious activity isn’t stopped, your IP reputation will tank quickly. Unfortunately, these attacks often slide under the radar, making it difficult to stop them while they are in progress. 

How to identify an IP reputation attack

IP reputation attacks can be difficult to detect, but certain red flags may indicate you're being targeted. Watch for these early warning indicators:

• Emails bouncing back: If you’re noticing more bounced emails than normal, email service providers could be blocking your address. 
• Increase in spam reports: If there’s a sudden influx in spam reports from your contacts, it’s an indication that hackers could be using your email address to send unwanted spam emails. 
• Unusual network activity: If you use network monitoring tools, look for strange spikes in outgoing traffic. This activity could indicate that your website has been compromised. 
• Web browser security warnings: If cybercriminals have compromised your IP address, web browsers may mark your site as unsafe and send security warnings to visitors.  
• Notifications from cybersecurity tools: Many tools monitor your IP reputation and warn you of any recent changes. If you receive a notification from these platforms, it’s worth digging deeper to see if your IP address has been compromised. 

How to prevent IP reputation attacks

Investing time and energy into your cybersecurity strategies helps protect your IP address from malicious outsiders. Here’s how to improve your IP reputation and reduce the risk of devastating attacks.

Build an email strategy

The first step to limiting your IP reputation risk is developing a smart email marketing strategy. Hackers can damage your reputation with targeted attacks, but you could also be hurting your IP reputation on your own with unintentionally spammy email campaigns. 

When launching your brand, you can’t dive head-first into a high-volume campaign. If your recipients are bombarded by emails from a sender they don’t know well, they could mark them as spam, hurting your IP address in the process. Instead, you’ll need to “warm up” your IP address by slowly increasing your email volume as interest grows. 

Implement firewalls and intrusion detection systems

Keeping malicious traffic out of your networks can help prevent hackers from accessing your IP address. A great place to start is by implementing a secure firewall. Firewalls filter both incoming and outgoing traffic and will alert you to any unusual changes in traffic patterns. You can also configure your firewall to block suspicious traffic based on your pre-determined parameters. 

You can also use an intrusion detection system to complement your firewall. Intrusion detection systems take traffic monitoring a step further, alerting system managers to any malicious actions or policy breaches. For example, you could use intrusion detection systems to alert you if someone is sending spam emails from your server. This will help you stop an IP reputation attack in its tracks, before the damaging spirals out of control. 

Stay vigilant for social engineering scams

Cybercriminals may use social engineering scams like phishing emails or fake websites to collect your IP address. If your team doesn’t know how to spot these scams in real time, they could accidentally expose your IP address. 

To prevent social engineering scams, stay up to date on the latest social engineering scams, and remain vigilant when opening emails or clicking on links. If necessary, provide regular cybersecurity training for your team as well. 

How to recover your IP reputation if you suffer an attack

If you’ve been targeted in an IP reputation attack, acting quickly can help secure your systems and minimize further damage. Follow this step-by-step guide to restore your reputation.

1. 1.Review your system’s activity logs to identify the source of the attack and determine which IP addresses have been compromised. 
2. 2.Disconnect the compromised pieces of hardware from the rest of your systems. This includes any server, computer, or mobile device currently connected to the compromised IP address. It’s essential to do this as quickly as possible to prevent further damage to your reputation. 
3. 3.Check to see if any vulnerable data could have been exposed in the attack, such as financial information or intellectual property. If so, contact your customers right away to inform them of the data breach, taking care to remain compliant with local or industry regulations. 
4. 4.Re-secure any systems that have been compromised. This step could involve changing passwords, updating devices, or switching to new servers. You may also need to change the security settings on your network. 
5. 5.Use an IP address checker to see your current IP reputation and determine if you have been blocklisted. If your IP address has been blocklisted, you will need to contact ISPs and email service providers individually to explain the situation and have your status updated. You may need to provide documentation proving that you were targeted and that the security issues have been resolved. 
6. 6.If your IP reputation has been damaged, but you are not blocklisted, you can slowly restore it over time by implementing a new email strategy. Pull back on high-volume email campaigns and switch to more targeted messages that are less likely to get marked as spam. 

How to improve your IP reputation

If your IP reputation has been damaged, you can follow these steps to repair it:

• Monitor your servers. Consistent monitoring helps you identify and respond to malicious activity right away. 
• Launch a new email strategy. Go back to the drawing board with your email campaigns. Focus on content that provides value for readers to prevent it being marked as spam. 
• Review your mailing lists. Remove active or disengaged users, as they are more likely to mark your messages as spam. 
• Segment your emails. With email segmentation, you can send targeted emails to different groups on your mailing lists, which can help with engagement. 
• Use separate email servers. Using separate servers for internal emails and marketing emails, so your internal communications don’t affect your IP reputation. 
• Switch to a dedicated IP. This way, your reputation isn’t tied to other senders, giving you more control over your IP reputation.

Note that the IP repair process takes time, and you’ll need to be consistent with your actions. Your reputation won’t be restored overnight, but you should see gradual improvement.