If you use any of the MSRBL DNSBLs, take note: For the second time since 2017, the domain msrbl.net has expired and its name servers are responding positively to any DNS request.
This has the net effect of the DNSBL "listing the world." If you use any MSRBL blocklist in your mail server, you're blocking all mail from any IP address in the whole world.
So....don't do that!
The MSRBL's website at msrbl.com is up and running, but the DNSBL zones are not under "dot com" -- they are under "dot net."
June 14, 2019 Update: Looks like the DNSBL has been restored and is no longer "listing the world."
All about DNSBLs, aka blocklists/blacklists // Since 2001 // Published by Al Iverson
Status of exitnodes.tor.dnsbl.sectoor.de: DEAD
As reported by Word to the Wise, the DNSBL at exitnodes.tor.dnsbl.sectoor.de seems to have gone extinct. Like has happened with other lists in the past, the domain now contains a wildcard DNS entry which is bad news for DNSBLs. This means that those folks who use this DNSBL to filter mail are going to get a match on every possible IP address in the world. Every possible IP address will show up as listed, even though it's not actually listed by the blocklist.
As a result, I strongly suggest that mail administrators stop using the exitnodes.tor.dnsbl.sectoor.de DNSBL immediately.
DNSBL lookup sites should stop including exitnodes.tor.dnsbl.sectoor.de in blocklist results; the information they display would be incorrect and would scare people into thinking that they are listed, when they are not.
I don't know much about this DNSBL. Based on its name, it seems to exist to allow people to block mail from servers that host TOR Exit Nodes. If you're receiving anonymized harassing mail, that might be something you'd want to block.
The Internet Archive suggests that this list has been around since at least February 7, 2005.
June 6, 2018 Update: The DNS "wildcard" entry has been removed. This should stop any false positive issues, and means that the list is no longer "listing the world." However, the blocklist is still offline, seemingly for good, and I still strongly suggest that mail admins cease use of this list immediately.
June 6, 2018 Update: The DNS "wildcard" entry has been removed. This should stop any false positive issues, and means that the list is no longer "listing the world." However, the blocklist is still offline, seemingly for good, and I still strongly suggest that mail admins cease use of this list immediately.
Status of dnsbl.cyberlogic.net: BROKEN
As reported on the mailop mailing list on Friday May 25, 2018, the blocking list at dnsbl.cyberlogic.net now contains a "wildcard" DNS entry, effectively listing the entire internet. If you use this DNSBL in your mail server configuration, you should remove it immediately, as it will impede your ability to receive legitimate mail.
New blocklist: SPFBL
Leonardo from SPFBL shared the following information with me and I thought it would be useful to share it here with folks.
Status of bad.psky.me: QUESTIONABLE
Noted and respected spam filterer Spamhaus is indicating that they believe the the Protected Sky (bad.psky.me) blocklist is "fraudulent." They report that Protected Sky is "an anonymously-run DNSBL service which was pirating [Spamhaus] data and republishing it as its own work." Spamhaus further indicates that Protected Sky doesn't follow DNSBL best practices as indicated in RFC6471.
Status of anonwhois.org: DEAD
I first blogged about the ANONWHOIS blocking list back in 2010. It was very useful to identify domains were ownership information was cloaked from the public. Why? Because many of us in the anti-spam and security community think that for a domain being used for commercial purposes, it isn't right to hide who the owner is. And this obstruction to transparency is often exploited by bad guys who send spam and malware, to try to make it harder to identify them.
Status of bl.spamcannibal.org: DEAD
Back in 2016, I used this page to report on a temporary system issue with the Spam Cannibal DNSBL.
Today (May 30, 2018) I'm updating this page to let folks know that they should immediately cease using the Spam Cannibal blocking list.The domain spamcannibal.org seems to have expired and been taken over by somebody else. If you decide to visit the website, be careful! It tried to get me to install what I assume to be malware.
If you use this DNSBL in your mail server configuration, you're probably now rejecting all mail, as the domain has a wildcard DNS entry. This kind of thing makes a blocklist look like it has listed the whole world. Every IP address checked usually shows up as listed.
The Spam Cannibal DNSBL has been around since at least 2003. It was started by a gentleman that I think prefers to be anonymous, so I'm choosing not to name him. It was basically spamtrap-driven, though I believe it would sometimes list /24 blocks of IP addresses in response to some spamtrap hits. It wasn't that widely used, but back in the old days, it often put the fear of god into marketing senders when seeing a hit against this list on their favorite DNSBL checking tool. This was also good in that it helped to drive marketer understanding of how sending to bad addresses can cause bad things to happen. As the list was primarily spamtrap-driven, it was mostly safe for hobbyist mail server use (in my opinion, anyway).
I reached out to the publisher of the Spam Cannibal DNSBL He let me know that the DNSBL is dead and gone. It is no longer an ongoing concern.
Fifteen years is a pretty good run, if you ask me. I wish him best of luck on any future projects.
May 31, 2018 update: The operator of Spam Cannibal is working with some smart folks to shut down the list in a graceful fashion. While there is no longer a "wildcard DNS" issue, the list is no longer being updated and is retired; you should still remove it from your mail server configuration.
Today (May 30, 2018) I'm updating this page to let folks know that they should immediately cease using the Spam Cannibal blocking list.
The Spam Cannibal DNSBL has been around since at least 2003. It was started by a gentleman that I think prefers to be anonymous, so I'm choosing not to name him. It was basically spamtrap-driven, though I believe it would sometimes list /24 blocks of IP addresses in response to some spamtrap hits. It wasn't that widely used, but back in the old days, it often put the fear of god into marketing senders when seeing a hit against this list on their favorite DNSBL checking tool. This was also good in that it helped to drive marketer understanding of how sending to bad addresses can cause bad things to happen. As the list was primarily spamtrap-driven, it was mostly safe for hobbyist mail server use (in my opinion, anyway).
I reached out to the publisher of the Spam Cannibal DNSBL He let me know that the DNSBL is dead and gone. It is no longer an ongoing concern.
Fifteen years is a pretty good run, if you ask me. I wish him best of luck on any future projects.
May 31, 2018 update: The operator of Spam Cannibal is working with some smart folks to shut down the list in a graceful fashion. While there is no longer a "wildcard DNS" issue, the list is no longer being updated and is retired; you should still remove it from your mail server configuration.
SURBL: Adding ABUSE sublist, deprecating SC & AB
The domain blocking list SURBL announced today that it is deprecating the SC (Spamcop) and AB (AbuseButler) sublists, migrating their data into a new ABUSE sublist. They note that the WS (Bill Stearns' sa-blacklist) sublist is also going to be migrated into ABUSE in 2016.
SURBL also recently announced the addition of SURBL-specific blocking notification messages to the popular SpamAssassin spam filtering software.
SURBL also recently announced the addition of SURBL-specific blocking notification messages to the popular SpamAssassin spam filtering software.
Status of no-more-funn.moensted.dk: DEAD
The "No More Funn" blocking list (DNSBL zone no-more-funn.moensted.dk) was run by a gentleman from Denmark using the alias dr. Jørgen Mash. First observed in 2002, listing criteria included spam sources, IP address ranges that appeared dynamic, bulk mailers not required confirmed opt-in (double opt-in) and more. It was easy for email service providers (ESPs) to end up listed there, and ESP clients would often ask about those listings because they would show up in DNSBL lookups, though it's not clear that the list was widely used for spam blocking.
At some point in 2012, the list was taken offline. At the end of 2015, the website reports that the list is still offline. Thus, I'm going to call this one "dead."
At some point in 2012, the list was taken offline. At the end of 2015, the website reports that the list is still offline. Thus, I'm going to call this one "dead."
What is blacklist.zap?
Here's a blast from the past: Remember blacklist.zap?
There were various "blacklist.zap" lists and they were all indicative of blocking when sending to mailboxes hosted behind "FrontBridge" anti-spam and security protection:
There were various "blacklist.zap" lists and they were all indicative of blocking when sending to mailboxes hosted behind "FrontBridge" anti-spam and security protection:
- The list 85.blacklist.zap specifically referred to FrontBridge's use of the Composite Blocking List (CBL). If you were blocked by 85.blacklist.zap, it meant that your sending IP address was listed on the CBL.
- The list 86.blacklist.zap specifically referred to FrontBridge's use of the Spamhaus Block List (SBL). If you were blocked by 86.blacklist.zap, it meant that your sending IP address was listed on the SBL.
- The list 87.blacklist.zap specifically referred to FrontBridge's use of the Spamhaus Exploits Block List (SBL). If you were blocked by 87.blacklist.zap, it meant that your sending IP address was listed on the XBL.
- The list 88.blacklist.zap specifically referred to FrontBridge's own internally-generated blacklist of sending IP addresses noted to be spammy, usually based on a high percentage of mail from that IP address being denoted as spammy.
FrontBridge was later acquired by Microsoft and I think it's been a long time since anybody has seen blacklist.zap blocking in a bounce message, but I thought it would be good to keep a record of this for posterity's sake.
Status of dnsbl.burnt-tech.com: DEAD
Uh-oh! On or about September 19th, the domain burnt-tech.com seems to have expired. Now when you visit the website, you are informed that the domain is for sale. Also, you'll now find a wildcard A record in DNS, meaning that any lookup of any host name in DNS under burnt-tech.com will result in a positive response being returned.
The net result here is that due to the domain now having a wildcard A record, any users of the Burnt Tech DNSBL now find that they are blocking all inbound mail. If you were using the dnsbl.burnt-tech.com blocking list to filter inbound spam, you'll need to remove it from your mail server or spam filter configuration immediately, as it is going to impede your ability to receive any mail.
Reviewing Internet Archive versions of the Burnt Tech DNSBL website, it appears that the list has been in action since at least 2006. From a 2015 archived copy of the website: "The Block List runs entirely automated and designed to avoid listings of spamtrap hits due to bounces of forged spam, virus bounces, and "real" mail servers emitting the occasional spam. It tries very hard to avoid listing legitimate mail sources. It does not attempt to list every possible spam source."
No other information was available regarding ownership, listing criteria or history of this DNSBL.
(H/T: Matthew Vernhout)
The net result here is that due to the domain now having a wildcard A record, any users of the Burnt Tech DNSBL now find that they are blocking all inbound mail. If you were using the dnsbl.burnt-tech.com blocking list to filter inbound spam, you'll need to remove it from your mail server or spam filter configuration immediately, as it is going to impede your ability to receive any mail.
Reviewing Internet Archive versions of the Burnt Tech DNSBL website, it appears that the list has been in action since at least 2006. From a 2015 archived copy of the website: "The Block List runs entirely automated and designed to avoid listings of spamtrap hits due to bounces of forged spam, virus bounces, and "real" mail servers emitting the occasional spam. It tries very hard to avoid listing legitimate mail sources. It does not attempt to list every possible spam source."
No other information was available regarding ownership, listing criteria or history of this DNSBL.
(H/T: Matthew Vernhout)
Status of truncate.gbudb.net: ALIVE
The "Truncate" DNSBL (zone truncate.gbudb.net) lists IPv4 addresses that have been observed transmitting "email containing spam, scams, viruses, or other malware based on statistics in the global GBUdb network." This "Good, Bad, Ugly database (GBUdb)" is a "real-time collaborative IP reputation system," based on statistics collected by email threat protection software Message Sniffer.
If you're listed on the Truncate DNSBL, can you request removal? No, explains the website. IP addresses are removed automatically, usually within a couple of days of the bad activity having ceased. They warn, however, that in some instances, if enough bad activity was denoted, it may take longer for an IP address to automatically disappear from their list.
Have any more information you'd like to share about this blocking list? Please feel free to contact me and I'll be happy to update this page with your additional information.
If you're listed on the Truncate DNSBL, can you request removal? No, explains the website. IP addresses are removed automatically, usually within a couple of days of the bad activity having ceased. They warn, however, that in some instances, if enough bad activity was denoted, it may take longer for an IP address to automatically disappear from their list.
Have any more information you'd like to share about this blocking list? Please feel free to contact me and I'll be happy to update this page with your additional information.
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