The GBUdb Truncate DNSBL is a fully automated IP blocklist that uses strict statistical criteria to list sending IPs that exclusively distribute malicious content such as spam, scams, and viruses.
GBUdb Truncate DNSBL is an IP-based Domain Name System Blocklist (DNSBL) that identifies IP addresses exclusively associated with sending harmful content. It operates under the zone truncate.gbudb.net. It is designed to be rfc5782 compliant, a standard for DNS-based blacklists.
The policy for this blacklist is extremely strict. An IP address is listed only when there is high confidence, based on statistical data from the global GBUdb network, that it sends spam, scams, viruses, or other malware. When a system queries this blocklist about an IP address, a return code of 127.0.0.2 confirms the listing. Due to its strict criteria, administrators can often safely reject connections from IPs on this list without a high risk of blocking legitimate email.
GBUdb Truncate DNSBL is operated by the GBUdb project. GBUdb stands for "Good, Bad, Ugly database" and functions as a real-time, collaborative IP reputation system. The system gathers data through the Message Sniffer engine, learning to identify the characteristics of content sent from various IP addresses across the internet. GBUdb uses this data to create security products, like the Truncate DNSBL, to help combat spam and malware.
Maintenance of the GBUdb Truncate DNSBL is completely automated. This means there are no provisions for manual removal or delisting requests. To be removed from this blacklist, the IP address in question must stop sending emails that trigger the listing criteria, such as spam or malware. Once the malicious activity ceases, the automated system will eventually remove the IP address from the list. There is no specific timeframe for this, as it depends on the system's ongoing data analysis.
Before your IP can be automatically delisted, you must first resolve the underlying cause of the problem. This involves investigating potential security issues like compromised user accounts, malware on your network, or misconfigured applications that are sending unwanted mail. Fixing the root cause is the only way to ensure permanent removal from this and other blocklists.
The impact of being listed on the GBUdb Truncate DNSBL is generally considered low. While any blocklist listing can negatively affect email deliverability, this particular blacklist is not as widely adopted as some larger, more influential ones. However, a listing should not be ignored. It serves as a clear warning that your IP address has a poor reputation and is actively sending problematic email. This can hurt your sender reputation and may lead to listings on other, more impactful blacklists if the issue is not addressed promptly.
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