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Questions tagged [spam-filter]

The tag has no usage guidance.

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4 views

ESET Mail Security for Linux as mail gateway/proxy for Synology mail server

It's been a really long time since I've been doing such stuff, but maybe others still do. I have a license for ESET Mail Security that I used for Exchange 2010, but now we're migrating to Synology's ...
0
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0answers
19 views

SpamAssassin rule to detect matching To and From headers?

I use a Proxmox mail gateway for my small business's emails (and also for several clients), but we have noticed an interesting uptick in emails which have a matching "To" and "From" address, always a '...
0
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1answer
19 views

why two spam policy apply on the same email

Recently, we made some Spam setting as below shown, but don't know why the result is, emails are prepended with 'spam' and move to junk mailbox at the same time. We want SCL 5 emails is prepended with ...
1
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1answer
108 views

Gmail detects emails as spam from domain with neutral reputation

I have a new domain and mail-in-a-box server set up correctly. Unfortunately, when sending to Gmail, it treats emails from my domain a a spam. The domain is not blacklisted and DNS settings are also ...
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0answers
91 views

Rejecting emails with mismatched Header/Envelop FROM

We've been receiving some spam/phishing emails that are managing to get through on occasion and the majority have a MAIL fROM our domain but their ENVELOPE from is whatever spammy address. My ...
0
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1answer
111 views

Postfix allow incoming mail for specified domain from specified ips

I am running a Postfix mail server. Some domains are configured that the DNS MX record is set to an antispam service. This service is forwarding the good mails to our mailserver. Some sender are ...
2
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1answer
127 views

Postfix reverse MX check

Is there any way to configure reverse MX check for Postfix to check incoming emails? I just noticed that most of our spam which are still coming true are sent (or seems to be sent) from properly ...
1
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1answer
159 views

Postfix - Send spam to different email address

I've researched for an answer to this question and can't find anything. I have Postfix running on Debian Stretch. I will soon be setting up Rspamd. Here's the logic of what I want to have happen ...
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0answers
77 views

Changing SpamAssassin's URIBL rule not to block email on query refued

I got an email rejected in Exim + SpamAssassin because of query refused by lookup.uribl.com. Message: Blacklisted URL in message. (example.com) in. See http://lookup.uribl.com. This, however, was an ...
0
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1answer
27 views

Incoming Email Server (I think) is Blocking Email Form

I’m not a server professional of IT person, so ignorance is admitted in terms of configuring servers. But this is why I am seeking direction from someone who knows more. When I build websites, it is ...
2
votes
1answer
2k views

Exchange office 365 transport rules to block spam when FROM doesn't match smtp.mailfrom or return path

I'm sure this type of question has been answered already so I apologize in advance, but I can't seem to find anything. I have spf, dkim, dmarc all setup so I'm not worried about outgoing spam, but I ...
0
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1answer
470 views

filtering spam emails with Chinese subject

A client have ton of Chinese spam. All look similar to this one: Return-Path: <15308409199@189.cn> X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on hotel492.dedicatedpanel.com X-...
0
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1answer
230 views

How do I get Courier Maildrop to log data?

Background I'm running Ubuntu 16.04 LTS on a virtual machine. It is the mail server for a small medical clinic. We are trying to move mail filtering from the client-side to the server-side, and I am ...
1
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1answer
510 views

How to block SendGrid spam with sendmail?

Sendgrid and MailChimp are the two biggest sources of spam captured in my spam-folder. I'd like to block them before they get there. Fortunately, in an effort to appear "legitimate" the spammers ...
0
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2answers
2k views

Exchange 2013 - Remove warning text from outgoing email body

I created a transport-rule in our Exchange server 2013 where it will add a warning text on top of email-body to all external incoming emails. This is to alert employees about potential risks in ...
1
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1answer
117 views

TXT entry in DNS for both gmail and amazon ses

It seems adding a TXT entry in DNS about Google is a good practice (when using gmail to send mail) to prevent being considered as Spammer. So I could add a TXT entry in my DNS records to: example.org ...
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0answers
18 views

Exchange rule to trigger on “From” addesses of format “email <email>”

We are receiving large email flow with an interesting pattern of "From" address. They forge body "From" address as "spoofed local email ". Example: From: user@domain.com <forged@foreigndomain.com&...
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0answers
48 views

Could two emails sent at the exact same time to the same user cause spam filtering?

we are setting up a mail service which will send emails periodically. There are two kinds of email. One which is sent three times a day (8, 13, 17 o'clock). Another which MAY be sent at 8am ...
4
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0answers
90 views

Combating a persistent spam list

We use Office 365 as our primary mail provider. We have an internal mail server that we use for relaying things like reports from our SSRS, scan to inbox for old scanners, etc. It is an IIS SMTP on ...
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2answers
412 views

SPF issue with different HELO FQDN

I am trying to setup SPF/DKIM/DMARC on my email server on a VPS. Here is my DNS configuration (DKIM & DMARC removed for readability) : @ 28800 A X.X.X.X @ ...
2
votes
1answer
3k views

Improve Spam Confidence Level (SCL) for outgoing emails

I have a postfix SMTP server on Ubuntu. I have valid SPF and DKIM records, as verified by the email header my customer received. Authentication-Results: spf=pass (sender IP is XXX.XXX.XXX.XXX) ...
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1answer
27 views

Watch Guard Total Security working over VPN

We have a warehouse and 4 other showroom locations. All the 4 locations are connect to the warehouse through a VPN. If we get a watch guard for each location and connect through a VPN. Would it be ...
0
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1answer
733 views

Unknown ACL condition/modifier in in EXIM configuration for Rspamd

I am trying to configure EXIM to use Rspamd as a spam filter. I am running Exim version 4.87 and installed Rpsam from the repositories using apt-get as explained here. Then I added the suggested ...
2
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0answers
624 views

Accept or not to accept DKIM signed emails on my smtp server which source DNS don't has signature [closed]

In the outgoing emails we use in our domains SPF + DKIM without any problem. But with the inbound emails some time ago we're receiving emails from some of our customers/suppliers signed with DKIM, ...
0
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1answer
64 views

What are the basic steps to start blocking spam on an internal Exchange 2016 server? [duplicate]

Recently I have taken over as both onsite IT and also head of our internal IT as the last IT guy resigned on my second day. Currently they just switched to an internal Exchange 2016 server and they're ...
0
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1answer
475 views

IIS 8.5 Request Filtering block referrer spam traffic

Recently I'm having a lot of requests that I see in google analytics from these domains (+25 others...): scanner-irvin.top scanner-viktor.top compliance-alex.top scanner-ivan.top scanner-jess.top ...
1
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1answer
126 views

smtpd_recipient_restrictions: Some RBLs working, but SBL isn't

I'm trying to set up postfix so that it uses blocklists to block spam. This is my restriction setting in main.cf: smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,...
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0answers
64 views

SpamExperts filtering outbound mail

I've got a hosted domain & mail server. It is attached—somehow—to a SpamExperts installation. I've been training the filter for years and it does a fine job filtering out the incoming garbage. ...
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votes
2answers
899 views

Using a subdomain for email address [closed]

I have recently acquired a domain which closely resembles my last name (basically there are two words in my name and the domain is only the second word). The plan was to use a subdomain in order to ...
0
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0answers
381 views

Exchange 2013 -Prevent Spam emails from outside but with my internal domain name

my apologies if this question was asked and answered previously. we have Exchange 2013 email server. We have been seeing some of the emails are coming from outside but using our own domain name which ...
1
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3answers
2k views

Exchange 2010 ignoring SPF record

we are using Exchange 2010 and have already setup SPF record for our authorized mail server IPs. As a test using our domain name i tried to send an e-mail from another computer on the internet which ...
0
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0answers
575 views

SMTP Mail delivery failed for URIBL query refused

I'm experiencing some trouble with a single recipient because his mail server refuse my email. This is the error reply: SMTP error from remote mail server after RCPT TO:<xxxx@xxx.xxx>: 554 5.7....
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3answers
2k views

What is DNS TXT record “mailru-verification”?

Sometimes I see this mailru-verification DNS record. I've Googled - and Yandexed ;) - but I found nothing about it. I suspected that is a kind of russian SPF implementation... dig example.com TXT ...
0
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0answers
195 views

Postfix selectively bypassing the spam

I have Centos 7 installed and postfix as MTA on the server. Here is my anti spam postfix additional configuration: # main.cf ANTI SPAM disable_vrfy_command = yes smtpd_delay_reject = yes ...
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votes
1answer
88 views

DKIM - DomainKey Identified Mail public key longer than 512 character [closed]

I've generated private key and public key using following commands. openssl genrsa -des3 -out server.key openssl rsa -in server.key -out server.key.insecure mv server.key server.key.secure mv server....
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2answers
987 views

How reliable is validating email domain by reverse DNS MX record checking [duplicate]

This question is not about how to protect against spam or validate a particular email user. But how reliable is validating emails domain (does it exists at all) by reverse dns. What are the pitfalls ...
0
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1answer
349 views

Spamassassin + Gmail + Mbox

If I give sa-learn Maildir mails to train it as spam, it takes them without problems, but when trying to use a mbox file containing spam emails from my personal Gmail account (using https://takeout....
0
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1answer
190 views

SPAM data set, suitable for SpamAssasin or not?

I want to train my SpamAssasin filter, and I've downloaded all SPAM tars from January 2015 to November 2015 from that site: untroubled.org/spam/ Also, I've downloaded my ham and SPAM emails from my ...
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0answers
25 views

postfix filter “Do you want to have more lovers?” [duplicate]

My postfix is currently set up to check email content and reject by keywords. However, I can't think of a good way to block this kind of emails: Return-Path: <gievcyopa@beamtele.com> Delivered-...
0
votes
1answer
102 views

ibm domino own user anti-spam control

I am investigating a way to control how many emails an authenticated user can send per day: For example, I would like to put a global limit per user to a maximum 1000 emails sent per day. Or a per ...
1
vote
1answer
90 views

How to configure SpamAssassin to set Atlassian JIRA notifigations to white list?

I have problem Atlassian JIRA email notifications. These notifications come to deleted by SpamAssassin some reason. So I need to know how to confirgure SpamAssassin to but these notications to ...
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0answers
93 views

Kolab 3 outbound mails spam detection

I installed Kolab on a local server and I need a way to allow it to reject spam mails before they are sent. One method that I found is to install postfix and spamassassin in another server and ...
2
votes
1answer
141 views

Postfix change add-on priority

I have just started to fight with Spam mails because of my new project. I will explain structure of that system. We have Postfix as MTA on relay server and fresh Spamassasian and Policyd(v2 ...
0
votes
2answers
1k views

use exim systemfilter to drop specific incoming and outgoing emails withou bounce message

i want to use systemfilter to ignore emails from and to a specific domain with the following rule: if ("$message_body:, $h_to:, $h_reply_to:, $sender_address" contains "example.com") then fail endif ...
0
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1answer
26 views

sbs 2008 exchange 2007 recipient filtering

We have an SBS 2008 server with exchange 2007 installed on it. We run a spamfilter in front of it. My problem is that whenever I use an invalid email address. invalid@mydomain.com it gets accepted by ...
1
vote
1answer
2k views

SpamAssassin with dovecot-antispam training

I'm trying to get dovecot-antispam working with SpamAssassin' sa-learn. This is my Dovecot configuration: antispam_backend = pipe antispam_trash = trash;Trash;Deleted Items; Deleted Messages ...
2
votes
1answer
74 views

Can IP reputation be affected due to automatic forwarding?

I am hitting a dead wall with the support team of my email hosting provider. The IP they assigned me was blacklisted and so sending emails to AOL.co.uk end up getting rejected. After several emails ...
1
vote
1answer
3k views

How to tell if razor is running?

I have a mailserver which is using amavis to do the spam testing (through spamassassin). Now I wanted to use razor and pyzor as well. I installed them and did the following: # su - amavis -s /bin/...
2
votes
1answer
1k views

Exchange 2013 IPBlockListProvider blocking some (but not all) matched IPs

I have configured our Exchange 2013 Edge Transport server to utilize several IPBlockListProviders including Spamhaus. While they work great most of the time, there are still some emails which despite ...
1
vote
1answer
163 views

relearn bayes autolearned spam when mails already processed by exchange

I'm using postfix with amavis and spamassassin to filter out spam before relaying everything to an exchange server. Regularly I got mails which weren't catched by spamassassin, even worse, they were ...