Aug 20, 2010 19:14 GMT  ·  By

The Spamhaus Project has issued an official statement to clarify that the addition of a Google-owned IP address range to its Spam Block List (SBL) targeted Google Docs and did not affect Gmail.

Spamhaus is one of the leading spam fighting organizations in the world and maintains several block lists, which are used by email providers, educational institutions, corporations and other entities to block malicious traffic.

Yesterday, the anti-spam outfit added 74.125.227.0/24, an IP range owned by Google, to its Spam Block List (SBL).

Referencing information provided by Web integrity monitoring vendor Sucuri Security, we subsequently reported that this decision affects Gmail.

"Recently some IT websites, including Softpedia and Sucuri, erroneously issued reports of Spamhaus' SBL blocking Gmail. These reports are not true," Spamhaus announced today via a statement posted on its website.

"Google's Gmail service has never been listed in, or affected by, any Spamhaus DNSBL, nor ever would be. Spamhaus quite simply will not list outbound mail servers of Google/Gmail or any giant freemail provider," the organization stressed.

The key in this clarification is the "outbound mail servers" part, because the whole confusion was caused by www.gmail.com responding to IPs in the blocked range.

Sucuri Security maintains a Web scanner, which performs several tests in order to determine if a website is malicious or not.

Part of that process is searching for the domain name and its corresponding IP against several blacklists like Google Safe Browsing, Phish Tank, Norton Safe Web, the Malware Domain List and apparently Spamhaus' Spam Block List (SBL).

Searching the SBL is great to determine if the IP address a domain points to is associated with spam activity, but ultimately this list's purpose is to be used to block spam emails not filter HTTP traffic.

And emails originating from Gmail go out through gmail-smtp-in.l.google.com and other servers that respond to IP addresses in other ranges.

Therefore, in conclusion, even if the 74.125.227.0/24 IP block does cover the www.gmail.com domain, it shouldn't have impacted neither Webmail access, nor email traffic.

By enstating this block Spamhaus was actually trying to force Google to clean malicious resources hosted on Google Docs, a service commonly abused by spammers.

"Some Google-owned server IPs hosting severe malicious spam problems - specifically Google's 'Google Docs' service - do get rightly listed in the Spamhaus SBL when Google does not take action fast enough to stop the serving of malicious sites via Google Docs," the organization explained.

This problem has since been resolved and the SBL entry was removed.