Questions tagged [blacklist]
A blacklist is a basic access control mechanism that rejects elements included in the list.
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Whitelist allowed IPs (in/out) using iptables
I have a few ip ranges to which I want my server to able to connect and users to connect from. Everything else should be blocked.
How should I do that with iptables?
My OS is Debian based linux ...
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Use IPtables or null route for blacklisting about 1 million IP addresses?
I've come across a situation where a client needs to blacklist a set of just under 1 million individual IP addresses (no subnets), and network performance is a concern. While I would conjecture that ...
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What are the best methods for catching snowshoe spam?
I'm using Smartermail for my small mailserver. We've been having a problem lately of getting waves of snowshoe spam that follow the same pattern. They come in batches of 3 or 4 at a time. The ...
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Which anti spam DNS blacklists should used?
i want to protect my mailserver with dns blacklists for fighting the spam.
there a so many blacklists out there.
currently i use:
ix.dnsbl.manitu.net
cbl.abuseat.org
bl.spamcop.net
safe.dnsbl.sorbs....
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Where to go to see if my IP is blacklisted as a SPAM
This has happened before and some mail servers will tell you that your IP has been blacklisted (RBL, CBL, etc) but I can't find that site to check anymore and searches result in a site that may or may ...
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How to remove ourselves from nudity blacklists? [duplicate]
We recently bought our domain. It turns out, two generations ago, it was a porn site.
Now we're still blocked in some filters, resulting in blocked pages at several corporate routers.
I'm now ...
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Where to place Nginx IP blacklist config file?
I have an Nginx web server hosting two sites. I created a blockips.conf file to blacklist IP addresses that are constantly probing the server and included this file in the nginx.conf file. However ...
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Check public DNS health and RFC compliance
Every now and again I like to run checks on my DNS servers to make sure they are running right and to RFC spec. I used to use the DNSTools website to do this as it gave me a pretty good picture of ...
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How to report spam to blacklists
Is there a central place to report spam to various blacklists ?
I regularly report to spamcop, but
I do not see the addresses I reported as listed. (I guess nobody else bothers with my regular ...
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Blocking apache access via user agent string
I've got a scripter who is using a proxy to attack a website I'm serving.
I've noticed that they tend to access the site via software with a certain common user agent string (i.e. http://www....
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Getting a domain name off of the blacklist
I have a friend who purchased a domain name recently that he found out (after buying it) is apparently blocked by many corporate firewalls or proxies b/c it's been tagged as porn by the blacklist db ...
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Why is my email server in AT&T's blacklist?
I just got this bounce message:
<████████@att.net>: host scc-mailrelay.att.net[204.127.208.75] said:
521-88.208.246.34 blocked by sbc:blacklist.mailrelay.att.net. 521 DNSRBL:
Blocked ...
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How Does DNSWL work? How can I gain better trust? [closed]
How does DNSWL work? It's clear to me when someone report a spam, but how can I gain a higher score/trust?
Do some companies report "good" servers? Or will the score go up with time without reporting ...
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How do I get my server off the ivmSIP/24 blacklist?
I checked my server IP using this tool:
http://www.mxtoolbox.com/SuperTool.aspx
It's come up on the ivmSIP/24 list.
What can I do to get my IP removed from this list? I have SPF records set to allow ...
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Refuse to send email to specific recipients with Postfix
So, right now I am halfway through trying to setup an outgoing-mail blacklist, by way of smtpd_recipient_restrictions.
The problem I am experiencing is that my test emails are being delivered when I ...
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Which DNS Black Lists would you recommend to discard spam in pre-queue?
There are many black lists out there, with bad and good reputations. Also, some people recommend to use RBL lists only in score-based systems (like spamassassin) while others (including commercial ...
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Spamassassin: Bypass /etc/resolv.conf DNS for querying DNSBL?
Question
Is there a way to let spamassassin bypass my linux system's dns servers to query DNSBLs?
Background Info
When my Server receives email, it is checked by spamassassin. One of this checks ...
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How to blacklist or whitelist lots or few ip ranges with ipset and iptables + fail2ban
EDIT:
It's astonishing how the urge to find a solution sometimes is sufficient to slowly but steadily lead one towards a solution. Also, the more often I reread my question in order to clarify it, I ...
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how to specify a partial domain in blacklist with SpamAssassin
is there a way to specify a partial domain in the spamassassin blacklist?
I get spam from something like [email protected] but I also get junk from [email protected]. if I specify @.xyz ...
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What is meant by '550 Relay not Permitted' when it comes to emails?
For the past few months, I have been emailing a company with no problems. They have been able to receive my emails and they have been responding.
A few days ago, they dropped me an email where my ...
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CBL This IP address is HELO'ing as "localhost.localdomain"
I am pretty lost here, my server somehow got into a blacklist. And I don't know why and how to solve it. Please take a look at the link below.
CBL List - click here
Anyone knows what is going on ...
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Postfix reject_rbl_client Blacklists Not Working
I have a mail server (iRedMail) that uses Postfix. I've been getting a lot of spam, so I modified the /etc/postfix/main.cf file and have the smtpd_recipient_restrictions set to this:
...
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Best way to use large IP blacklist to deny access to a web server?
Is there efficient and easy way to use IP blacklist (like this one, but perhaps 2-3 times larger, which can't be simplified to CIDRs much) to deny access to a web server (either lighttpd or Apache) ...
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Gmail.com detect mail as spam, but the server is not on any BlackList
I have an issue with Google. (GMail to be exact)
About 1 month ago, we had a security breach, and mail was relayed through our servers.
we got listed in almost ALL Black-Lists :(
we fixed the ...
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Customer's IP Listed on RBL - What steps do you use to prevent black listing?
Customer called saying their e-mail was bouncing from particular vendors. Investigated it and identified they were listed on more than one RBL/CBL. Restricted firewall to only allow traffic on port ...
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How do I tell Amazon SES their IP addresses are blacklisted?
Is there an official way to tell Amazon SES about blacklisting, and ask them to talk to the other company involved?
I have had emails disappear this week and last week (Ironport doesn't even send ...
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Why is my mail server blacklisted (graylisting failiure)?
My mail server was blacklisted. I fail to understand why. It was first greylisted and than it became blacklisted. Greylisting is a practice of temporary rejecting mail coming from one mail server to ...
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Postfix restrict recipients
how can I configure postfix to allow sending to a certain (external) domain only?
I'm already using check_recipient_access. Content of my /etc/postfix/recipients_restrictions:
domain.com OK
My (...
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Blacklisting: IP's or domains?
I am implementing a blacklisting system on my website that monitors contact forms for suspicious usage (both spam content and excessive frequency).
When I find somebody / robot that meets my criteria ...
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hotmail blacklist and rDNS questions
My company has recently purchased a VPS for email and webhosting. I am not an expert on email authentication but here is my story.
After the VPS was purchased we started receiving bouncebacks with ...
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False IP blacklisting on CBL and Spamhaus ZEN
I've gone thru this: Spamhaus XBL keeps adding my IP
I'm managing the server 23.239.30.81 on Ubuntu using Postfix.
Since last 6 months or so I started forwarding all my:
Cron Daemon logs
Postfix ...
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How do I prevent mail from my Exchange server from being blocked?
Recently one of our client machines was infected with a virus and I believe was spamming addresses in the user's contact list. Since then our server has been appearing on blacklists and it has been ...
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SMTP: Which IP should I monitor?
I use a relay server to deliver external mails. I use relay server's IP in SPF record. But I'm not sure about blacklist monitoring/checking. Should I check main server's IP or relay's IP?
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Black Hole DNS on Windows DNS Server
I am looking at configuring our Windows DNS Servers for some type of DNS based blackhole operation. Ideally, we would be able to use feeds from MalwareDomains.com or the like. I was curious how one ...
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How does IP blacklisting work on virtualized/shared hosting?
I have read that many blocks of IP addresses associated with Amazon EC2 have been blacklisted by various ISPs. Therefore, even if you never sent spam yourself, emails you send from an Amazon instance ...
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Unable to delist from SORBS blacklist [closed]
The IP address of one of my servers has been blacklisted by SORBS. The delisting process on their website does not work correctly for me.
Asides from contacting SORBS directly, is there anything ...
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Postfix: Resend 'hard' bounces
I had a number of messages get rejected by the recipient's mail server with a status 550 code due to an IP address blacklist. I've sorted the problem that caused the host to become blacklisted, and ...
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postfix not blocking blacklisted IP
I have a postfix/dovecot server running inside a docker container, and I would like to block some IP addresses from connecting to my SMTP server. I have the following in /etc/postfix/main.cf:
...
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How to unblacklist an IP at Google?
I own a small business with two servers for webhosting. When setting up the primary (CentOS 5.5 + WHM, secondary is WHM DNS Only) server I kinda messed up the firewall, so the hackers could send stuff ...
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How to check, if IPs in your network are blacklisted?
I would like actively monitor, if any of my network IPs are on blacklists.
Here I would like to collect links to instructions, how to sync blacklists, which allows that.
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How to unblacklist an email at Microsoft/OutLook/hotmail
When trying to send email to clients who use Hotmail/Outlook/etc type email addresses, I get the following error:
SMTP error from remote mail server after RCPT TO:[email protected]:
550 5.4.1 Recipient ...
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Email Server IP Address is Blacklisted
we have a Zimbra Mail server that was being used for 2 months now.
the last week we faced a problem that the Public IP that was being used for our mail server started to be blacklisted and we couldn't ...
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Eliminate Email Blacklist by switching IPs and Servers
We are a legitimate company. We have had some issues in the past with Virus attacks/ Spam bots getting our email server blacklisted.
After the most recent attack I have been tasked at coming up with ...
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Are only IP-Addresses Blacklisted or also Domains?
Unfortunately one of the forms of my website was used to send completely sensless spammails. As I found out through "http://mxtoolbox.com" that my IP-address is listed on two blacklists, I want to set ...
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Why the ip can't be banned with postfix blacklist?
vim /etc/postfix/main.cf
smtpd_recipient_restrictions = check_sender_access hash:/etc/postfix/access
Add some ips in /etc/postfix/access
vim /etc/postfix/access
86.111.171.141 REJECT
191.96.249....
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Best practices on how to send emails on clients behalf and avoid being black listed
I am starting a business providing some online customer relationship management functionality. I want to allow my clients to create their own email lists.
I also want to allow my clients to be able ...
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Can I create a website blacklist with Group Policy?
I can create "whitelist" functionality for blocking all sites and allowing some via the GP setting: User Configuration > Windows Settings > Internet Explorer Maintenance > Connection/Proxy ...
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Symantec adds email server IP address to blacklist without any proof - how to fight them?
Recently noticed that email server IP address 88.119.185.129 is added to Symantec email blacklist. This IP is clean, not listed at any blacklists. The email server is not open relay, all emails are ...
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Postfix thinks IP is in blacklist, but is not actually listed in blacklist
Got a bit of a weird problem here with Postfix.
Been getting a whole bunch of notices where fail2ban has banned 69.164.196.21 (ryujin.darkdna.net) for failures against Postfix.
Here is a relevant ...
2
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1
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How do I implement IP-based export restrictions for my data stored on Amazon S3?
A little background: Corporate wants to make our downloads unavailable to U.S. export-restricted countries like North Korea, Iran, Syria, etc. Restriction by IP-block is considered good enough. (Yes, ...
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