Have you been blocked?
All blocklists are researched and managed by The Spamhaus Project.
Simply click on the link below, which will take you to the Project’s IP and Domain Reputation Checker. From here you will be able to enter your IP or Domain and begin your request for removal.
Please note that the Project’s IP and Domain Reputation Checker is the only place where removals are handled.
IT and security teams consistently face multiple business challenges. Discover how our solutions can help overcome some of those issues.
From processing issues, to email-borne threats our blocklists easily integrate with your current email set-up to improve anti-spam & anti-virus email filtering.
Employ our threat intelligence to increase visibility across security events, reveal potential weaknesses in your network, and threats to your brand.
Stay on top of the latest threats and proactively combat botnet infections, and other forms of abuse, with our solutions.
From clicking on phishing emails to visiting malware dropper sites, our threat intelligence provides automatic protection for your users.
Our products provide additional layers of security for networks and email. They also present security teams with additional insight into malicious behavior.
Border Gateway Protocol (BGP)
Block the worst of the worst at your network edge, taking advantage of your existing BGP-capable routers. Configuration only takes minutes.
Data Query Service (DQS)
Benefit from industry-leading real time blocklists. These DNSBLs easily plug into your existing email infrastructure to block spam and other email threats.
A powerful research tool to investigate relationships between internet infrastructures. Quickly pivot to new areas of concern to rapidly investigate potential threats.
Immediately block connections to dangerous sites, including phishing and malware dropper websites. A ‘set and forget’ solution.
Spamhaus Intelligence API
Threat intelligence data in API format to enable users to easily integrate metadata relating to threats with their own applications, programs, and products.
A wide range of datasets, providing multiple layers of protection. They can be plugged directly into your existing hardware, making them an affordable choice.
Border Gateway Protocol (BGP) Feeds
Do Not Route Or Peer (DROP) and Botnet Controller List (BCL) datafeeds can peer with your existing BGP-capable router.
Domain (DBL), Zero Reputation (ZRD) and Hash blocklists (HBL) enable you to block content in emails, filtering out a higher rate of email-borne threats.
Data for Investigation
Passive DNS and extended datasets give you additional information on internet resources. They provide deeper insights into incidents and possible threats.
DNS Firewall Threat Feeds
A wide range of feeds to apply to your DNS recursive server. Choose the right level of protection for your organization.
Spam (SBL), Policy (PBL), Exploits (XBL) and Auth (AuthBL) blocklists allow you to filter email from IPs associated with spam, botnets, and other threats.
Find out more about us.
Learn more about Spamhaus; who we are, and what we do.
Find out who we work with and how you can become a Spamhaus Partner.
Discover a wide range of blog posts, case studies and reports.
Commonly asked questions about Spamhaus products and processes.
The Blocklist Tester
A tool to help you check if your servers are correctly configured to use Spamhaus DNSBLs.
In depth information about the technical details and implementation of our products.
Posted by The Spamhaus Team on 18 May 2020
Hash blocklists focus on email content. They help you filter malicious email from large ISPs that can't be filtered by IP or domain blocklists. Additionally, they can be used to block emails containing malware files and cryptowallet addresses. Here's how they work, and the value they bring to your email security infrastructure.
IP & Domain Blocklists (DNSBLs) are very effective at filtering malicious emails. However, they do have one big limitation: How do you block an email sent from a compromised account at Gmail, Hotmail or any other large email service provider (ESP)?
You can’t block all email from these ESPs. But, by creating a hash of a compromised email account, emails from the hacked account can be blocked, while protecting the privacy of its owner. Additionally, this approach can be expanded to cover other areas of concern.
In simple terms, a Hash Blocklist (HBL) is a list of cryptographic hashes derived from malicious content. Spamhaus’ HBL has been designed to be extendable i.e., subsets of the list can detail different areas of malicious content. Compromised email addresses, cryptowallets and malware files are all included in Spamhaus’ HBL. Let’s take a look at these areas in more detail.
Let’s imagine a case where Vicky’s Gmail account is compromised. An attacker can use Vicky’s credentials to send an email message coming directly from Vicky. The usual ‘hooks’ used in email reputation systems won’t work because the message is coming from Gmails’ server, a legitimate server providing services to millions of people. Reviewing the reputation of the sending IP address won’t help, nor will the sending domain.
However, when Spamhaus assesses an email account to be compromised, we will associate a hash to that specific email address. This allows users to query the HBL and block emails that are coming from that hacked email account, that otherwise would have gone undetected.
Similarly to a malicious email address, where we have seen a file to be associated with malware, we assign that file with a cryptographic hash. So, even if no malicious IPs or domains can be associated with the email message containing the malware file, the Malware HBL can be queried for that hash in the “file” context. The Spamhaus HBL return codes will tell you one of two things:
A malware file can have a hash associated with it and be listed on the Malware HBL within only 30 seconds of detection. This is as a result of our researchers’ advanced collection and agile dissemination methods.
Think of the “sextortion” scam emails, which are currently so prevalent. You know the ones – they look something like the one below:
The sextortion email includes a bitcoin address of where the victim is to send money. Even if the sending email doesn’t trigger a rejection based on IP or domain reputation, the bitcoin address can be used to determine that the email is malicious in nature and result in the email being blocked anyway.
Virtually anything that can be extracted from an email message can be hashed. This data then can be used to create a new sub-list, thus increasing the number of reputational hooks available to you. The Spamhaus HBL helps postmasters and filtering software identify and block emerging threats now and, due to its extensible nature, well into the future.
Spamhaus’ Data Query Service (DQS) is an affordable and effective solution to protect your email infrastructure and users.
Using your existing email protection solution, you will be able to block spam and other related threats including malware, ransomware, and phishing emails.
The service has never failed and utilizes the longest established DNSBLs in the industry.
7 July 2020
Watch this on-demand webinar with Emanuele and Matt from The Spamhaus Project to learn how to increase your block rates, using content blocklists. These DNSBLs an help you block malicious email from large ISPs you previously wouldn't have been able to block.
18 May 2020
It's a well-known fact that filtering emails using IP blocklists (DNSBLs) blocks the vast majority of malicious emails. It's effective and economical, using minimal computational power. So why should you also use domain and hash blocklists for filtering?
29 October 2019
As IT budgets and resources are squeezed it's understandable to shop around, be it for hardware, software, or threat intelligence data, for that matter. But beware...not all email blocklists (DNSBLs) are equal.