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0Spam Network Block List (NBL)

The 0Spam Network Block List (NBL) is an IP-based blacklist that lists entire Class C network ranges that are sources of high-volume spam trap hits, but it should be used with caution as it is also likely to block legitimate email.

0Spam Network Block List (NBL)
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Check your domain or IP against 92 blocklists.
0spam.org logo0Spam
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8086 Consultancy
abuse.ro logoabuse.ro
Blocklist icon
Abusix
wiki.alphanet.ch logoALPHANETanonmails.de logoAnonmails
Blocklist icon
Barracuda Networks
www.blockedservers.com logoBLOCKEDSERVERSdnsbl.calivent.com.pe logoCalivent Networkswww.spamcop.net logoCisco
Blocklist icon
dan.me.uk
Blocklist icon
DrMx
Blocklist icon
DroneBL
rbl.efnetrbl.org logoEFnet
Blocklist icon
Fabel
Blocklist icon
GBUdb
Blocklist icon
ImproWare
Blocklist icon
JIPPG Technologies
Blocklist icon
Junk Email Filter
www.justspam.org logoJustSpamwww.kempt.net logoKempt.net
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Mail Baby
Blocklist icon
Mailspike
www.nordspam.com logoNordSpamwww.nosolicitado.org logoNoSolicitado
Blocklist icon
nsZones
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RedHawk
rv-soft.info logoRV-SOFT Technology
Blocklist icon
Schulte
www.scientificspam.net logoScientific Spam
Blocklist icon
Spam Eating Monkey
www.spamhaus.org logoSpamhauspsbl.org logoSpamikazewww.spamrats.com logoSpamRATSspfbl.net logoSPFBLsuomispam.net logoSuomispam
Blocklist icon
SURBL
www.usenix.org.uk logoSystem 5 Hostingwww.team-cymru.com logoTeam Cymru
Blocklist icon
UCEPROTECT
uribl.com logoURIBLwww.blocklist.de logowww.blocklist.de Fail2Ban-Reporting Servicezapbl.net logoZapBL
Blocklist icon
Brukalai.lt
0spam.org logo0Spam
Blocklist icon
8086 Consultancy
abuse.ro logoabuse.ro
Blocklist icon
Abusix
wiki.alphanet.ch logoALPHANETanonmails.de logoAnonmails
Blocklist icon
Barracuda Networks
www.blockedservers.com logoBLOCKEDSERVERSdnsbl.calivent.com.pe logoCalivent Networkswww.spamcop.net logoCisco
Blocklist icon
dan.me.uk
Blocklist icon
DrMx
Blocklist icon
DroneBL
rbl.efnetrbl.org logoEFnet
Blocklist icon
Fabel
Blocklist icon
GBUdb
Blocklist icon
ImproWare
Blocklist icon
JIPPG Technologies
Blocklist icon
Junk Email Filter
www.justspam.org logoJustSpamwww.kempt.net logoKempt.net
Blocklist icon
Mail Baby
Blocklist icon
Mailspike
www.nordspam.com logoNordSpamwww.nosolicitado.org logoNoSolicitado
Blocklist icon
nsZones
Blocklist icon
RedHawk
rv-soft.info logoRV-SOFT Technology
Blocklist icon
Schulte
www.scientificspam.net logoScientific Spam
Blocklist icon
Spam Eating Monkey
www.spamhaus.org logoSpamhauspsbl.org logoSpamikazewww.spamrats.com logoSpamRATSspfbl.net logoSPFBLsuomispam.net logoSuomispam
Blocklist icon
SURBL
www.usenix.org.uk logoSystem 5 Hostingwww.team-cymru.com logoTeam Cymru
Blocklist icon
UCEPROTECT
uribl.com logoURIBLwww.blocklist.de logowww.blocklist.de Fail2Ban-Reporting Servicezapbl.net logoZapBL
Blocklist icon
Brukalai.lt
0spam.org logo0Spam
Blocklist icon
8086 Consultancy
abuse.ro logoabuse.ro
Blocklist icon
Abusix
wiki.alphanet.ch logoALPHANETanonmails.de logoAnonmails
Blocklist icon
Barracuda Networks
www.blockedservers.com logoBLOCKEDSERVERSdnsbl.calivent.com.pe logoCalivent Networkswww.spamcop.net logoCisco
Blocklist icon
dan.me.uk
Blocklist icon
DrMx
Blocklist icon
DroneBL
rbl.efnetrbl.org logoEFnet
Blocklist icon
Fabel
Blocklist icon
GBUdb
Blocklist icon
ImproWare
Blocklist icon
JIPPG Technologies
Blocklist icon
Junk Email Filter
www.justspam.org logoJustSpamwww.kempt.net logoKempt.net
Blocklist icon
Mail Baby
Blocklist icon
Mailspike
www.nordspam.com logoNordSpamwww.nosolicitado.org logoNoSolicitado
Blocklist icon
nsZones
Blocklist icon
RedHawk
rv-soft.info logoRV-SOFT Technology
Blocklist icon
Schulte
www.scientificspam.net logoScientific Spam
Blocklist icon
Spam Eating Monkey
www.spamhaus.org logoSpamhauspsbl.org logoSpamikazewww.spamrats.com logoSpamRATSspfbl.net logoSPFBLsuomispam.net logoSuomispam
Blocklist icon
SURBL
www.usenix.org.uk logoSystem 5 Hostingwww.team-cymru.com logoTeam Cymru
Blocklist icon
UCEPROTECT
uribl.com logoURIBLwww.blocklist.de logowww.blocklist.de Fail2Ban-Reporting Servicezapbl.net logoZapBL
Blocklist icon
Brukalai.lt
0spam.org logo0Spam
Blocklist icon
8086 Consultancy
abuse.ro logoabuse.ro
Blocklist icon
Abusix
wiki.alphanet.ch logoALPHANETanonmails.de logoAnonmails
Blocklist icon
Barracuda Networks
www.blockedservers.com logoBLOCKEDSERVERSdnsbl.calivent.com.pe logoCalivent Networkswww.spamcop.net logoCisco
Blocklist icon
dan.me.uk
Blocklist icon
DrMx
Blocklist icon
DroneBL
rbl.efnetrbl.org logoEFnet
Blocklist icon
Fabel
Blocklist icon
GBUdb
Blocklist icon
ImproWare
Blocklist icon
JIPPG Technologies
Blocklist icon
Junk Email Filter
www.justspam.org logoJustSpamwww.kempt.net logoKempt.net
Blocklist icon
Mail Baby
Blocklist icon
Mailspike
www.nordspam.com logoNordSpamwww.nosolicitado.org logoNoSolicitado
Blocklist icon
nsZones
Blocklist icon
RedHawk
rv-soft.info logoRV-SOFT Technology
Blocklist icon
Schulte
www.scientificspam.net logoScientific Spam
Blocklist icon
Spam Eating Monkey
www.spamhaus.org logoSpamhauspsbl.org logoSpamikazewww.spamrats.com logoSpamRATSspfbl.net logoSPFBLsuomispam.net logoSuomispam
Blocklist icon
SURBL
www.usenix.org.uk logoSystem 5 Hostingwww.team-cymru.com logoTeam Cymru
Blocklist icon
UCEPROTECT
uribl.com logoURIBLwww.blocklist.de logowww.blocklist.de Fail2Ban-Reporting Servicezapbl.net logoZapBL
Blocklist icon
Brukalai.lt
0spam.org logo0Spam
Blocklist icon
8086 Consultancy
abuse.ro logoabuse.ro
Blocklist icon
Abusix
wiki.alphanet.ch logoALPHANETanonmails.de logoAnonmails
Blocklist icon
Barracuda Networks
www.blockedservers.com logoBLOCKEDSERVERSdnsbl.calivent.com.pe logoCalivent Networkswww.spamcop.net logoCisco
Blocklist icon
dan.me.uk
Blocklist icon
DrMx
Blocklist icon
DroneBL
rbl.efnetrbl.org logoEFnet
Blocklist icon
Fabel
Blocklist icon
GBUdb
Blocklist icon
ImproWare
Blocklist icon
JIPPG Technologies
Blocklist icon
Junk Email Filter
www.justspam.org logoJustSpamwww.kempt.net logoKempt.net
Blocklist icon
Mail Baby
Blocklist icon
Mailspike
www.nordspam.com logoNordSpamwww.nosolicitado.org logoNoSolicitado
Blocklist icon
nsZones
Blocklist icon
RedHawk
rv-soft.info logoRV-SOFT Technology
Blocklist icon
Schulte
www.scientificspam.net logoScientific Spam
Blocklist icon
Spam Eating Monkey
www.spamhaus.org logoSpamhauspsbl.org logoSpamikazewww.spamrats.com logoSpamRATSspfbl.net logoSPFBLsuomispam.net logoSuomispam
Blocklist icon
SURBL
www.usenix.org.uk logoSystem 5 Hostingwww.team-cymru.com logoTeam Cymru
Blocklist icon
UCEPROTECT
uribl.com logoURIBLwww.blocklist.de logowww.blocklist.de Fail2Ban-Reporting Servicezapbl.net logoZapBL
Blocklist icon
Brukalai.lt

What is 0Spam network block list (NBL)?

The 0Spam Network Block List (NBL) is a real-time IP-based Domain Name System Blocklist (DNSBL). It was formerly known as the FusionZero DNSBL, and some older system configurations may still reference the old name. This blacklist (or blocklist) is designed to identify networks that are sources of high-volume spam trap hits.

The policy and technical details of the 0Spam Network Block List (NBL) are important for senders to understand:

  • Network-level blocking: The list includes entire Class C network blocks if they are found to be unresponsive to abuse complaints or are a consistent source of spam.
  • Use with caution: The operators advise that this blocklist should not be used alone. Because it lists entire networks, there is a higher probability that legitimate email may originate from a listed network range.
  • Listing criteria: Listings are based on spam trap data. Networks with a high volume of email hitting spam traps are candidates for this blacklist.

Who runs 0Spam network block list (NBL)?

The 0Spam Network Block List (NBL) is run by the 0spam project. Their stated mission is to work towards a spam-free internet by combining machine learning with an intelligent anti-spam framework. The project is primarily supported by donations from the IT and system administrator community.

0spam also offers additional services for network administrators, including IP notification services that alert them when a managed IP is listed. This service can provide a 24-hour grace period before a listing goes public, allowing administrators time to address the issue. They also send abuse notifications to the designated abuse contacts for IP addresses found sending spam.

How do I get removed and delisted from 0Spam network block list (NBL)?

Before requesting removal from any blacklist, including this one, you must first identify and resolve the root cause of the listing. Failure to do so will likely result in being relisted quickly. Once you have fixed the problem, you can request delisting.

  • Identify the source of spam and stop it completely.
  • 0spam recommends enforcing double opt-in for all mailing lists, as hitting a spam trap is impossible with a confirmed opt-in process.
  • Ensure your sending practices are CAN-SPAM compliant.
  • Visit the 0spam removal page and create an account. The removal process is free.
  • You can request removal for one IP address every three hours. This limit is in place to prevent automated abuse of the system.

For long-term listings: In rare cases involving repeated abuse, a network block might be placed on a long-term listing. To be removed from this, you must stop all sources of spam from the network for at least 60 days before you can apply for a manual removal.

What's the impact of being listed on 0Spam network block list (NBL)?

The impact of being on the 0Spam Network Block List (NBL) is considered medium. The main reason for this is its policy of listing entire Class C networks. If your IP address is on a network that has been listed on this blocklist, your emails could be blocked by any mail server using this list, even if your specific IP has never sent spam. This can cause significant deliverability issues for legitimate senders who share network infrastructure with bad actors. The list's own warning that it should be used with caution suggests that while its adoption may not be as widespread as other major blacklists, its impact can be broad and indiscriminate for those affected.

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