TechTheft Conferr Blacklist
TechTheft Conferr is a private IP blacklist and blocklist that logs IPs with missing or broken DNS records to help prevent network abuse.
Updated on 17 Jun 2026: We updated this guide to clarify Conferr lookup evidence and the rDNS fixes needed before delisting.
Summarize with
Check if you are listed on TechTheft Conferr Blacklist
And 143 other blocklists.
Spamhaus
0Spam
Cisco
NoSolicitado
URIBL
abuse.ro
ALPHANET
Anonmails
Ascams
BLOCKEDSERVERS
Calivent Networks
EFnet
JustSpam
Kempt.net
NordSpam
RV-SOFT Technology
Scientific Spam
Spamikaze
SpamRATS
SPFBL
Suomispam
System 5 Hosting
Team Cymru
Validity
www.blocklist.de Fail2Ban-Reporting Service
ZapBL
2stepback.dk
Fayntic Services
ORB UK
technoirc.org
TechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftWhat is TechTheft Conferr blacklist?
The TechTheft Conferr blacklist is an IP-based DNSBL and DNS-based blocklist that operates automatically from server and firewall logs. Its DNS zone is conferr.bl.techtheft.info. TechTheft describes Conferr as a private blacklist intended for internal use by trusted subscribers, with subscriptions by invitation only.
The main reasons for an IP address being added to this blocklist (blacklist) are technical: no reverse DNS (rDNS), no PTR record, or DNS records that do not resolve cleanly. For mail servers, the PTR hostname should be valid and should resolve in a way that matches the sending infrastructure. Subscribers can use Conferr as a connection-level filter, so a listed IP can be rejected before message content or DMARC checks are evaluated.
Who runs TechTheft Conferr blacklist?
The blocklist is run by TechTheft, an organization that describes its work as fighting "Hi-Technology Theft," including spam, viral attacks, DDoS attacks, and IP hijacking. TechTheft's published positioning is aggressive: it prefers stopping abuse at the source rather than only filtering unwanted traffic after it arrives.
For Conferr, that operating model matters because the blacklist/blocklist is not positioned as a broad public reputation feed. It is a private DNSBL for participating administrators, so senders should confirm that a bounce or mail server log, including notes from the recipient administrator, names the Conferr zone before treating it as the cause of a delivery problem.
How to check a TechTheft Conferr listing
For a DNSBL lookup, reverse the IP address and append the zone name. For example, 192.0.2.45 becomes 45.2.0.192.conferr.bl.techtheft.info. Because Conferr is private, unauthorized DNS queries can return no answer or be refused, so the most reliable evidence is an SMTP rejection, mail server log, or recipient administrator note that names the zone.
Example DNSBL lookupbash
dig +short 45.2.0.192.conferr.bl.techtheft.info A dig +short 45.2.0.192.conferr.bl.techtheft.info TXT
- Treat a positive A response or TXT response as evidence that the IP is listed, then record the exact response before changing DNS or requesting a re-test.
- Treat NXDOMAIN, an empty answer, SERVFAIL, or REFUSED carefully because private access controls can hide the result from non-subscribers.
- Compare the listing evidence with current PTR, forward DNS, abuse contact, and sending logs so the fix targets the reason for the listing.
How do I get removed and delisted from TechTheft Conferr blacklist?
Removal from the TechTheft Conferr blacklist can happen automatically because IPs are re-tested at irregular intervals. You can also request a manual re-test, but do that after correcting the DNS or abuse-handling issue that caused the listing.
Use this checklist before requesting delisting:
- Resolve open abuse reports tied to the IP address. If the listing followed spam, scanning, malware, or abusive traffic, stop the traffic and keep the evidence needed to show it has ended.
- Publish and monitor a working abuse@ mailbox for the domain or IP space. If abuse contacts are missing or ignored, a manual re-test is less likely to help.
- Fix reverse DNS for the sending IP. Configure a valid PTR record, make sure the hostname exists in forward DNS, and avoid generic or broken hostnames.
- Confirm mail authentication for the same sending source. Suped's DMARC reporting can help identify whether the IP is sending authorized mail, whether SPF and DKIM pass, and whether DMARC produces the expected result before you ask for a re-test.
- Request a manual re-test only after the technical fixes are live in DNS. Keep the exact IP address and the relevant rejection text or lookup result ready for the request.
What's the impact of being listed on TechTheft Conferr blacklist?
The impact of being listed on the TechTheft Conferr blacklist is usually limited but specific. Because it is a private blocklist available only to trusted subscribers by invitation, it is not a broad public blacklist used across the whole email ecosystem. The practical impact is concentrated at organizations that query this zone during SMTP handling or firewall decisions.
If those organizations are important recipients, the impact can still be material. A Conferr listing can cause connection-level rejection or a temporary need to route mail through a correctly configured sending IP until the original IP passes re-testing.
Other TechTheft blocklists
TechTheft Bad Whois Blacklist
Organization
TechTheft
Zone
bad.whois.bl.techtheft.info
Type
Domain
Impact
Inactive
Delisting
Manual
TechTheft Blacklist
Organization
TechTheft
Zone
bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Bogon Blacklist
Organization
TechTheft
Zone
bogon.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Domain Blacklist
Organization
TechTheft
Zone
domain.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Expanded Blacklist
Organization
TechTheft
Zone
expanded.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft ISP Blacklist
Organization
TechTheft
Zone
isp.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Nana Blacklist
Organization
TechTheft
Zone
nana.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Other Blacklist
Organization
TechTheft
Zone
other.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Robot Blacklist
Organization
TechTheft
Zone
robot.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Scanning Blacklist
Organization
TechTheft
Zone
scanning.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Source Blacklist
Organization
TechTheft
Zone
source.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Support Blacklist
Organization
TechTheft
Zone
support.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Virus Blacklist
Organization
TechTheft
Zone
virus.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Watchlist Blacklist
Organization
TechTheft
Zone
watchlist.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
TechTheft Web Blacklist
Organization
TechTheft
Zone
web.bl.techtheft.info
Type
IP
Impact
Inactive
Delisting
Manual
